Merge branch 'master' of github.com:taosdata/TDengine into test/chr

cmake/define.inc

@@ -117,10 +117,14 @@ IF (TD_LINUX)
     ADD_DEFINITIONS(-D_TD_NINGSI_60)
     MESSAGE(STATUS "set ningsi macro to true")
   ENDIF ()
-  
-  SET(DEBUG_FLAGS "-O0 -g3 -DDEBUG")
+
+  IF (TD_MEMORY_SANITIZER)
+    SET(DEBUG_FLAGS "-fsanitize=address -fsanitize=undefined -fno-sanitize-recover=all -fsanitize=float-divide-by-zero -fsanitize=float-cast-overflow -fno-sanitize=null -fno-sanitize=alignment -static-libasan -O0 -g3 -DDEBUG")
+  ELSE ()
+    SET(DEBUG_FLAGS "-O0 -g3 -DDEBUG")
+  ENDIF ()
   SET(RELEASE_FLAGS "-O3 -Wno-error")
-  
+
   IF (${COVER} MATCHES "true")
     MESSAGE(STATUS "Test coverage mode, add extra flags")
     SET(GCC_COVERAGE_COMPILE_FLAGS "-fprofile-arcs -ftest-coverage")
@@ -139,7 +143,11 @@ IF (TD_DARWIN_64)
   ADD_DEFINITIONS(-DUSE_LIBICONV)
   MESSAGE(STATUS "darwin64 is defined")
   SET(COMMON_FLAGS "-std=gnu99 -Wall -Werror -Wno-missing-braces -fPIC -msse4.2 -D_FILE_OFFSET_BITS=64 -D_LARGE_FILE")
-  SET(DEBUG_FLAGS "-O0 -g3 -DDEBUG")
+  IF (TD_MEMORY_SANITIZER)
+    SET(DEBUG_FLAGS "-fsanitize=address -fsanitize=undefined -fno-sanitize-recover=all -fsanitize=float-divide-by-zero -fsanitize=float-cast-overflow -fno-sanitize=null -fno-sanitize=alignment -O0 -g3 -DDEBUG")
+  ELSE ()
+    SET(DEBUG_FLAGS "-O0 -g3 -DDEBUG")
+  ENDIF ()
   SET(RELEASE_FLAGS "-Og")
   INCLUDE_DIRECTORIES(${TD_COMMUNITY_DIR}/deps/cJson/inc)
   INCLUDE_DIRECTORIES(${TD_COMMUNITY_DIR}/deps/lz4/inc)
@@ -157,7 +165,11 @@ IF (TD_WINDOWS)
     IF (MSVC AND (MSVC_VERSION GREATER_EQUAL 1900))
       SET(COMMON_FLAGS "${COMMON_FLAGS} /Wv:18")
     ENDIF ()
-    SET(DEBUG_FLAGS "/Zi /W3 /GL")
+    IF (TD_MEMORY_SANITIZER)
+      SET(DEBUG_FLAGS "/fsanitize=address /Zi /W3 /GL")
+    ELSE ()
+      SET(DEBUG_FLAGS "/Zi /W3 /GL")
+    ENDIF ()
     SET(RELEASE_FLAGS "/W0 /O3 /GL")
   ENDIF ()
 
@@ -166,7 +178,7 @@ IF (TD_WINDOWS)
   INCLUDE_DIRECTORIES(${TD_COMMUNITY_DIR}/deps/regex)
   INCLUDE_DIRECTORIES(${TD_COMMUNITY_DIR}/deps/wepoll/inc)
   INCLUDE_DIRECTORIES(${TD_COMMUNITY_DIR}/deps/MsvcLibX/include)
-ENDIF () 
+ENDIF ()
 
 IF (TD_WINDOWS_64)
   ADD_DEFINITIONS(-D_M_X64)

cmake/input.inc

@@ -78,3 +78,8 @@ SET(TD_BUILD_JDBC TRUE)
 IF (${BUILD_JDBC} MATCHES "false")
   SET(TD_BUILD_JDBC FALSE)
 ENDIF ()
+
+SET(TD_MEMORY_SANITIZER FALSE)
+IF (${MEMORY_SANITIZER} MATCHES "true")
+  SET(TD_MEMORY_SANITIZER TRUE)
+ENDIF ()

src/client/inc/tsclient.h

@@ -405,6 +405,7 @@ typedef struct SSqlObj {
 
 typedef struct SSqlStream {
   SSqlObj *pSql;
+  void *  cqhandle;  // stream belong to SCQContext handle
   const char* dstTable;
   uint32_t streamId;
   char     listed;

src/client/src/tscParseInsert.c

@@ -466,6 +466,10 @@ int tsParseOneRow(char **str, STableDataBlocks *pDataBlocks, SSqlCmd *pCmd, int1
 
       int32_t cnt = 0;
       int32_t j = 0;
+      if (sToken.n >= TSDB_MAX_BYTES_PER_ROW) {
+        return tscSQLSyntaxErrMsg(pCmd->payload, "too long string", sToken.z);
+      }
+      
       for (uint32_t k = 1; k < sToken.n - 1; ++k) {
         if (sToken.z[k] == '\\' || (sToken.z[k] == delim && sToken.z[k + 1] == delim)) {
             tmpTokenBuf[j] = sToken.z[k + 1];
@@ -705,7 +709,7 @@ static int32_t doParseInsertStatement(SSqlCmd* pCmd, char **str, STableDataBlock
   }
 
   code = TSDB_CODE_TSC_INVALID_SQL;
-  char tmpTokenBuf[16*1024] = {0};  // used for deleting Escape character: \\, \', \"
+  char tmpTokenBuf[TSDB_MAX_BYTES_PER_ROW] = {0};  // used for deleting Escape character: \\, \', \"
 
   int32_t numOfRows = 0;
   code = tsParseValues(str, dataBuf, maxNumOfRows, pCmd, &numOfRows, tmpTokenBuf);

src/client/src/tscProfile.c

@@ -19,6 +19,7 @@
 #include "ttimer.h"
 #include "tutil.h"
 #include "taosmsg.h"
+#include "tcq.h"
 
 #include "taos.h"
 
@@ -294,24 +295,34 @@ int tscBuildQueryStreamDesc(void *pMsg, STscObj *pObj) {
   return msgLen;
 }
 
-void tscKillConnection(STscObj *pObj) {
-  pthread_mutex_lock(&pObj->mutex);
+// cqContext->dbconn is killed then call this callback
+void cqConnKilledNotify(void* handle, void* conn) {
+  if (handle == NULL || conn == NULL){
+    return ;
+  } 
 
-  SSqlObj *pSql = pObj->sqlList;
-  while (pSql) {
-    pSql = pSql->next;
-  }
-  
+  SCqContext* pContext = (SCqContext*) handle;
+  if (pContext->dbConn == conn){
+    atomic_store_ptr(&(pContext->dbConn), NULL);
+  } 
+}
 
+void tscKillConnection(STscObj *pObj) {
+  // get stream header by locked
+  pthread_mutex_lock(&pObj->mutex);
   SSqlStream *pStream = pObj->streamList;
+  pthread_mutex_unlock(&pObj->mutex);
+
   while (pStream) {
     SSqlStream *tmp = pStream->next;
+    // set associate variant to NULL
+    cqConnKilledNotify(pStream->cqhandle, pObj);
+    // taos_close_stream function call pObj->mutet lock , careful death-lock
     taos_close_stream(pStream);
     pStream = tmp;
   }
 
-  pthread_mutex_unlock(&pObj->mutex);
-
   tscDebug("connection:%p is killed", pObj);
   taos_close(pObj);
 }
+

src/client/src/tscSQLParser.c

@@ -314,7 +314,9 @@ int32_t tscToSQLCmd(SSqlObj* pSql, struct SSqlInfo* pInfo) {
         }
         
       } else if (pInfo->type == TSDB_SQL_DROP_DNODE) {
-        pzName->n = strdequote(pzName->z);
+        if (pzName->type == TK_STRING) {
+          pzName->n = strdequote(pzName->z);
+        }
         strncpy(pCmd->payload, pzName->z, pzName->n);
       } else {  // drop user/account
         if (pzName->n >= TSDB_USER_LEN) {
@@ -392,7 +394,9 @@ int32_t tscToSQLCmd(SSqlObj* pSql, struct SSqlInfo* pInfo) {
       }
 
       SStrToken* id = taosArrayGet(pInfo->pMiscInfo->a, 0);
-      id->n = strdequote(id->z);
+      if (id->type == TK_STRING) {
+        id->n = strdequote(id->z);
+      }
       break;
     }
 
@@ -1987,6 +1991,7 @@ int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int32_t col
   const char* msg7 = "normal table can not apply this function";
   const char* msg8 = "multi-columns selection does not support alias column name";
   const char* msg9 = "diff can no be applied to unsigned numeric type";
+  const char* msg10 = "parameter is out of range [1, 100]";
 
   switch (functionId) {
     case TSDB_FUNC_COUNT: {
@@ -2374,7 +2379,7 @@ int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int32_t col
 
         int64_t nTop = GET_INT32_VAL(val);
         if (nTop <= 0 || nTop > 100) {  // todo use macro
-          return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg5);
+          return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg10);
         }
 
         // todo REFACTOR
@@ -6674,7 +6679,8 @@ int32_t doCheckForStream(SSqlObj* pSql, SSqlInfo* pInfo) {
   const char* msg5 = "sql too long";  // todo ADD support
   const char* msg6 = "from missing in subclause";
   const char* msg7 = "time interval is required";
-  
+  const char* msg8 = "the first column should be primary timestamp column";
+   
   SSqlCmd*    pCmd = &pSql->cmd;
   SQueryInfo* pQueryInfo = tscGetQueryInfoDetail(pCmd, 0);
   assert(pQueryInfo->numOfTables == 1);
@@ -6731,8 +6737,26 @@ int32_t doCheckForStream(SSqlObj* pSql, SSqlInfo* pInfo) {
     return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg2);
   }
 
-  if (!tscIsProjectionQuery(pQueryInfo) && pQueryInfo->interval.interval == 0) {
-    return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg7);
+  // project query primary column must be timestamp type
+  if (tscIsProjectionQuery(pQueryInfo)) {
+    size_t size = tscSqlExprNumOfExprs(pQueryInfo);
+    // check zero
+    if(size == 0) {
+      return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg8);
+    }
+
+    // check primary column is timestamp
+    SSqlExpr* pSqlExpr = tscSqlExprGet(pQueryInfo, 0);
+    if(pSqlExpr == NULL) {
+      return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg8);
+    }
+    if( pSqlExpr->colInfo.colId != PRIMARYKEY_TIMESTAMP_COL_INDEX) {
+      return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg8);
+    }
+  } else {
+    if (pQueryInfo->interval.interval == 0) {
+      return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg7);
+    }    
   }
 
   // set the created table[stream] name

src/client/src/tscStream.c

@@ -141,6 +141,10 @@ static void tscProcessStreamTimer(void *handle, void *tmrId) {
 
   pStream->numOfRes = 0;  // reset the numOfRes.
   SSqlObj *pSql = pStream->pSql;
+  // pSql ==  NULL  maybe killStream already called
+  if(pSql == NULL) {
+    return ;
+  }
   SQueryInfo* pQueryInfo = tscGetQueryInfoDetail(&pSql->cmd, 0);
   tscDebug("0x%"PRIx64" add into timer", pSql->self);
 
@@ -336,8 +340,12 @@ static void tscSetRetryTimer(SSqlStream *pStream, SSqlObj *pSql, int64_t timer)
   if (pStream->isProject) {
     int64_t now = taosGetTimestamp(pStream->precision);
     int64_t etime = now > pStream->etime ? pStream->etime : now;
-
-    if (pStream->etime < now && now - pStream->etime > tsMaxRetentWindow) {
+    int64_t maxRetent = tsMaxRetentWindow * 1000;
+    if(pStream->precision == TSDB_TIME_PRECISION_MICRO) {
+      maxRetent *= 1000;
+    }
+         
+    if (pStream->etime < now && now - pStream->etime > maxRetent) {
       /*
        * current time window will be closed, since it too early to exceed the maxRetentWindow value
        */
@@ -662,7 +670,7 @@ void cbParseSql(void* param, TAOS_RES* res, int code) {
 }
 
 TAOS_STREAM *taos_open_stream_withname(TAOS *taos, const char* dstTable, const char *sqlstr, void (*fp)(void *param, TAOS_RES *, TAOS_ROW row),
-                              int64_t stime, void *param, void (*callback)(void *)) {
+                              int64_t stime, void *param, void (*callback)(void *), void* cqhandle) {
   STscObj *pObj = (STscObj *)taos;
   if (pObj == NULL || pObj->signature != pObj) return NULL;
 
@@ -695,6 +703,7 @@ TAOS_STREAM *taos_open_stream_withname(TAOS *taos, const char* dstTable, const c
   pStream->callback = callback;
   pStream->param = param;
   pStream->pSql = pSql;
+  pStream->cqhandle = cqhandle;
   pSql->pStream = pStream;
   pSql->param = pStream;
   pSql->maxRetry = TSDB_MAX_REPLICA;
@@ -735,7 +744,7 @@ TAOS_STREAM *taos_open_stream_withname(TAOS *taos, const char* dstTable, const c
 
 TAOS_STREAM *taos_open_stream(TAOS *taos, const char *sqlstr, void (*fp)(void *param, TAOS_RES *, TAOS_ROW row),
                               int64_t stime, void *param, void (*callback)(void *)) {  
-  return taos_open_stream_withname(taos, "", sqlstr, fp, stime, param, callback);
+  return taos_open_stream_withname(taos, "", sqlstr, fp, stime, param, callback, NULL);
 }
 
 void taos_close_stream(TAOS_STREAM *handle) {

src/common/src/tglobal.c

@@ -817,6 +817,16 @@ static void doInitGlobalConfig(void) {
   cfg.unitType = TAOS_CFG_UTYPE_NONE;
   taosInitConfigOption(cfg);
 
+  cfg.option = "precision";
+  cfg.ptr = &tsTimePrecision;
+  cfg.valType = TAOS_CFG_VTYPE_INT8;
+  cfg.cfgType = TSDB_CFG_CTYPE_B_CONFIG | TSDB_CFG_CTYPE_B_SHOW;
+  cfg.minValue = TSDB_MIN_PRECISION;
+  cfg.maxValue = TSDB_MAX_PRECISION;
+  cfg.ptrLength = 0;
+  cfg.unitType = TAOS_CFG_UTYPE_NONE;
+  taosInitConfigOption(cfg);
+
   cfg.option = "comp";
   cfg.ptr = &tsCompression;
   cfg.valType = TAOS_CFG_VTYPE_INT8;
@@ -887,6 +897,16 @@ static void doInitGlobalConfig(void) {
   cfg.unitType = TAOS_CFG_UTYPE_NONE;
   taosInitConfigOption(cfg);
 
+  cfg.option = "cachelast";
+  cfg.ptr = &tsCacheLastRow;
+  cfg.valType = TAOS_CFG_VTYPE_INT8;
+  cfg.cfgType = TSDB_CFG_CTYPE_B_CONFIG | TSDB_CFG_CTYPE_B_SHOW;
+  cfg.minValue = TSDB_MIN_DB_CACHE_LAST_ROW;
+  cfg.maxValue = TSDB_MAX_DB_CACHE_LAST_ROW;
+  cfg.ptrLength = 0;
+  cfg.unitType = TAOS_CFG_UTYPE_NONE;
+  taosInitConfigOption(cfg);
+
   cfg.option = "mqttHostName";
   cfg.ptr = tsMqttHostName;
   cfg.valType = TAOS_CFG_VTYPE_STRING;

src/common/src/tvariant.c

@@ -74,7 +74,7 @@ void tVariantCreate(tVariant *pVar, SStrToken *token) {
 
     case TSDB_DATA_TYPE_BINARY: {
       pVar->pz = strndup(token->z, token->n);
-      pVar->nLen = strdequote(pVar->pz);
+      pVar->nLen = strRmquote(pVar->pz, token->n);
       break;
     }
     

src/connector/jdbc/src/main/java/com/taosdata/jdbc/AbstractDatabaseMetaData.java

@@ -12,6 +12,9 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
     private final static int DRIVER_MAJAR_VERSION = 2;
     private final static int DRIVER_MINOR_VERSION = 0;
 
+    private String precision = "ms";
+    private String database;
+
     public boolean allProceduresAreCallable() throws SQLException {
         return false;
     }
@@ -493,102 +496,105 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
 
     public abstract ResultSet getTables(String catalog, String schemaPattern, String tableNamePattern, String[] types) throws SQLException;
 
-    protected ResultSet getTables(String catalog, String schemaPattern, String tableNamePattern, String[] types, Connection connection) throws SQLException {
-        try (Statement stmt = connection.createStatement()) {
-            if (catalog == null || catalog.isEmpty())
-                return null;
-
-            ResultSet databases = stmt.executeQuery("show databases");
-            String dbname = null;
-            while (databases.next()) {
-                dbname = databases.getString("name");
-                if (dbname.equalsIgnoreCase(catalog))
-                    break;
-            }
-            databases.close();
-            if (dbname == null)
-                return null;
+    private List<ColumnMetaData> buildGetTablesColumnMetaDataList() {
+        List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
+        columnMetaDataList.add(buildTableCatalogMeta(1));          // 1. TABLE_CAT
+        columnMetaDataList.add(buildTableSchemaMeta(2));           // 2. TABLE_SCHEM
+        columnMetaDataList.add(buildTableNameMeta(3));             // 3. TABLE_NAME
+        columnMetaDataList.add(buildTableTypeMeta(4));             // 4. TABLE_TYPE
+        columnMetaDataList.add(buildRemarksMeta(5));                // 5. remarks
+        columnMetaDataList.add(buildTypeCatMeta(6));                // 6. TYPE_CAT
+        columnMetaDataList.add(buildTypeSchemaMeta(7));             // 7. TYPE_SCHEM
+        columnMetaDataList.add(buildTypeNameMeta(8));               // 8. TYPE_NAME
+        columnMetaDataList.add(buildSelfReferencingColName(9));     // 9. SELF_REFERENCING_COL_NAME
+        columnMetaDataList.add(buildRefGenerationMeta(10));         // 10. REF_GENERATION
+        return columnMetaDataList;
+    }
+
+    private ColumnMetaData buildTypeCatMeta(int colIndex) {
+        ColumnMetaData col6 = new ColumnMetaData();
+        col6.setColIndex(colIndex);
+        col6.setColName("TYPE_CAT");
+        col6.setColType(Types.NCHAR);
+        return col6;
+    }
+
+    private ColumnMetaData buildTypeSchemaMeta(int colIndex) {
+        ColumnMetaData col7 = new ColumnMetaData();
+        col7.setColIndex(colIndex);
+        col7.setColName("TYPE_SCHEM");
+        col7.setColType(Types.NCHAR);
+        return col7;
+    }
+
+    private ColumnMetaData buildTypeNameMeta(int colIndex) {
+        ColumnMetaData col8 = new ColumnMetaData();
+        col8.setColIndex(colIndex);
+        col8.setColName("TYPE_NAME");
+        col8.setColType(Types.NCHAR);
+        return col8;
+    }
+
+    private ColumnMetaData buildSelfReferencingColName(int colIndex) {
+        ColumnMetaData col9 = new ColumnMetaData();
+        col9.setColIndex(colIndex);
+        col9.setColName("SELF_REFERENCING_COL_NAME");
+        col9.setColType(Types.NCHAR);
+        return col9;
+    }
+
+    private ColumnMetaData buildRefGenerationMeta(int colIndex) {
+        ColumnMetaData col10 = new ColumnMetaData();
+        col10.setColIndex(colIndex);
+        col10.setColName("REF_GENERATION");
+        col10.setColType(Types.NCHAR);
+        return col10;
+    }
 
-            stmt.execute("use " + dbname);
-            DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
-            List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
-            ColumnMetaData col1 = new ColumnMetaData();
-            col1.setColIndex(1);
-            col1.setColName("TABLE_CAT");
-            col1.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col1);
-            ColumnMetaData col2 = new ColumnMetaData();
-            col2.setColIndex(2);
-            col2.setColName("TABLE_SCHEM");
-            col2.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col2);
-            ColumnMetaData col3 = new ColumnMetaData();
-            col3.setColIndex(3);
-            col3.setColName("TABLE_NAME");
-            col3.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col3);
-            ColumnMetaData col4 = new ColumnMetaData();
-            col4.setColIndex(4);
-            col4.setColName("TABLE_TYPE");
-            col4.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col4);
-            ColumnMetaData col5 = new ColumnMetaData();
-            col5.setColIndex(5);
-            col5.setColName("REMARKS");
-            col5.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col5);
-            ColumnMetaData col6 = new ColumnMetaData();
-            col6.setColIndex(6);
-            col6.setColName("TYPE_CAT");
-            col6.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col6);
-            ColumnMetaData col7 = new ColumnMetaData();
-            col7.setColIndex(7);
-            col7.setColName("TYPE_SCHEM");
-            col7.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col7);
-            ColumnMetaData col8 = new ColumnMetaData();
-            col8.setColIndex(8);
-            col8.setColName("TYPE_NAME");
-            col8.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col8);
-            ColumnMetaData col9 = new ColumnMetaData();
-            col9.setColIndex(9);
-            col9.setColName("SELF_REFERENCING_COL_NAME");
-            col9.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col9);
-            ColumnMetaData col10 = new ColumnMetaData();
-            col10.setColIndex(10);
-            col10.setColName("REF_GENERATION");
-            col10.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col10);
-            resultSet.setColumnMetaDataList(columnMetaDataList);
+    protected ResultSet getTables(String catalog, String schemaPattern, String tableNamePattern, String[] types, Connection connection) throws SQLException {
+        if (catalog == null || catalog.isEmpty())
+            return null;
+        if (!isAvailableCatalog(connection, catalog))
+            return new EmptyResultSet();
 
-            List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
+        DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
+        // set column metadata list
+        resultSet.setColumnMetaDataList(buildGetTablesColumnMetaDataList());
+        // set row data
+        List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
+        try (Statement stmt = connection.createStatement()) {
+            stmt.execute("use " + catalog);
             ResultSet tables = stmt.executeQuery("show tables");
             while (tables.next()) {
                 TSDBResultSetRowData rowData = new TSDBResultSetRowData(10);
-                rowData.setString(0, dbname);   //table_cat
-                rowData.setString(1, null); //TABLE_SCHEM
-                rowData.setString(2, tables.getString("table_name"));   //TABLE_NAME
-                rowData.setString(3, "TABLE");  //TABLE_TYPE
-                rowData.setString(4, "");   //REMARKS
+                rowData.setStringValue(1, catalog);                                     //TABLE_CAT
+                rowData.setStringValue(2, null);                                 //TABLE_SCHEM
+                rowData.setStringValue(3, tables.getString("table_name"));  //TABLE_NAME
+                rowData.setStringValue(4, "TABLE");                              //TABLE_TYPE
+                rowData.setStringValue(5, "");                                   //REMARKS
                 rowDataList.add(rowData);
             }
-
             ResultSet stables = stmt.executeQuery("show stables");
             while (stables.next()) {
                 TSDBResultSetRowData rowData = new TSDBResultSetRowData(10);
-                rowData.setString(0, dbname);   //TABLE_CAT
-                rowData.setString(1, null); //TABLE_SCHEM
-                rowData.setString(2, stables.getString("name"));    //TABLE_NAME
-                rowData.setString(3, "TABLE");  //TABLE_TYPE
-                rowData.setString(4, "STABLE"); //REMARKS
+                rowData.setStringValue(1, catalog);                                  //TABLE_CAT
+                rowData.setStringValue(2, null);                              //TABLE_SCHEM
+                rowData.setStringValue(3, stables.getString("name"));    //TABLE_NAME
+                rowData.setStringValue(4, "TABLE");                           //TABLE_TYPE
+                rowData.setStringValue(5, "STABLE");                          //REMARKS
                 rowDataList.add(rowData);
             }
             resultSet.setRowDataList(rowDataList);
-            return resultSet;
         }
+        return resultSet;
+    }
+
+    private ColumnMetaData buildTableTypeMeta(int colIndex) {
+        ColumnMetaData col4 = new ColumnMetaData();
+        col4.setColIndex(colIndex);
+        col4.setColName("TABLE_TYPE");
+        col4.setColType(Types.NCHAR);
+        return col4;
     }
 
     public ResultSet getSchemas() throws SQLException {
@@ -597,25 +603,24 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
 
     public abstract ResultSet getCatalogs() throws SQLException;
 
+    private List<ColumnMetaData> buildTableTypesColumnMetadataList() {
+        List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
+        columnMetaDataList.add(buildTableTypeMeta(1));
+        return columnMetaDataList;
+    }
+
     public ResultSet getTableTypes() throws SQLException {
         DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
         // set up ColumnMetaDataList
-        List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
-        ColumnMetaData colMetaData = new ColumnMetaData();
-        colMetaData.setColIndex(0);
-        colMetaData.setColName("TABLE_TYPE");
-        colMetaData.setColSize(10);
-        colMetaData.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-        columnMetaDataList.add(colMetaData);
-        resultSet.setColumnMetaDataList(columnMetaDataList);
+        resultSet.setColumnMetaDataList(buildTableTypesColumnMetadataList());
 
         // set up rowDataList
         List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
         TSDBResultSetRowData rowData = new TSDBResultSetRowData(1);
-        rowData.setString(0, "TABLE");
+        rowData.setStringValue(1, "TABLE");
         rowDataList.add(rowData);
         rowData = new TSDBResultSetRowData(1);
-        rowData.setString(0, "STABLE");
+        rowData.setStringValue(1, "STABLE");
         rowDataList.add(rowData);
         resultSet.setRowDataList(rowDataList);
 
@@ -625,278 +630,330 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
     public abstract ResultSet getColumns(String catalog, String schemaPattern, String tableNamePattern, String columnNamePattern) throws SQLException;
 
     protected ResultSet getColumns(String catalog, String schemaPattern, String tableNamePattern, String columnNamePattern, Connection conn) {
-        try (Statement stmt = conn.createStatement()) {
-            if (catalog == null || catalog.isEmpty())
-                return null;
-
-            ResultSet databases = stmt.executeQuery("show databases");
-            String dbname = null;
-            while (databases.next()) {
-                dbname = databases.getString("name");
-                if (dbname.equalsIgnoreCase(catalog))
-                    break;
-            }
-            databases.close();
-            if (dbname == null)
-                return null;
+        if (catalog == null || catalog.isEmpty())
+            return null;
+        if (!isAvailableCatalog(conn, catalog))
+            return new EmptyResultSet();
 
-            stmt.execute("use " + dbname);
-            DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
-            // set up ColumnMetaDataList
-
-            List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
-            // TABLE_CAT
-            ColumnMetaData col1 = new ColumnMetaData();
-            col1.setColIndex(1);
-            col1.setColName("TABLE_CAT");
-            col1.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col1);
-            // TABLE_SCHEM
-            ColumnMetaData col2 = new ColumnMetaData();
-            col2.setColIndex(2);
-            col2.setColName("TABLE_SCHEM");
-            col2.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col2);
-            // TABLE_NAME
-            ColumnMetaData col3 = new ColumnMetaData();
-            col3.setColIndex(3);
-            col3.setColName("TABLE_NAME");
-            col3.setColSize(193);
-            col3.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col3);
-            // COLUMN_NAME
-            ColumnMetaData col4 = new ColumnMetaData();
-            col4.setColIndex(4);
-            col4.setColName("COLUMN_NAME");
-            col4.setColSize(65);
-            col4.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col4);
-            // DATA_TYPE
-            ColumnMetaData col5 = new ColumnMetaData();
-            col5.setColIndex(5);
-            col5.setColName("DATA_TYPE");
-            col5.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col5);
-            // TYPE_NAME
-            ColumnMetaData col6 = new ColumnMetaData();
-            col6.setColIndex(6);
-            col6.setColName("TYPE_NAME");
-            col6.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col6);
-            // COLUMN_SIZE
-            ColumnMetaData col7 = new ColumnMetaData();
-            col7.setColIndex(7);
-            col7.setColName("COLUMN_SIZE");
-            col7.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col7);
-            // BUFFER_LENGTH, not used
-            ColumnMetaData col8 = new ColumnMetaData();
-            col8.setColIndex(8);
-            col8.setColName("BUFFER_LENGTH");
-            columnMetaDataList.add(col8);
-            // DECIMAL_DIGITS
-            ColumnMetaData col9 = new ColumnMetaData();
-            col9.setColIndex(9);
-            col9.setColName("DECIMAL_DIGITS");
-            col9.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col9);
-            // add NUM_PREC_RADIX
-            ColumnMetaData col10 = new ColumnMetaData();
-            col10.setColIndex(10);
-            col10.setColName("NUM_PREC_RADIX");
-            col10.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col10);
-            // NULLABLE
-            ColumnMetaData col11 = new ColumnMetaData();
-            col11.setColIndex(11);
-            col11.setColName("NULLABLE");
-            col11.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col11);
-            // REMARKS
-            ColumnMetaData col12 = new ColumnMetaData();
-            col12.setColIndex(12);
-            col12.setColName("REMARKS");
-            col12.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col12);
-            // COLUMN_DEF
-            ColumnMetaData col13 = new ColumnMetaData();
-            col13.setColIndex(13);
-            col13.setColName("COLUMN_DEF");
-            col13.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col13);
-            //SQL_DATA_TYPE
-            ColumnMetaData col14 = new ColumnMetaData();
-            col14.setColIndex(14);
-            col14.setColName("SQL_DATA_TYPE");
-            col14.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col14);
-            //SQL_DATETIME_SUB
-            ColumnMetaData col15 = new ColumnMetaData();
-            col15.setColIndex(15);
-            col15.setColName("SQL_DATETIME_SUB");
-            col15.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col15);
-            //CHAR_OCTET_LENGTH
-            ColumnMetaData col16 = new ColumnMetaData();
-            col16.setColIndex(16);
-            col16.setColName("CHAR_OCTET_LENGTH");
-            col16.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col16);
-            //ORDINAL_POSITION
-            ColumnMetaData col17 = new ColumnMetaData();
-            col17.setColIndex(17);
-            col17.setColName("ORDINAL_POSITION");
-            col17.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col17);
-            // IS_NULLABLE
-            ColumnMetaData col18 = new ColumnMetaData();
-            col18.setColIndex(18);
-            col18.setColName("IS_NULLABLE");
-            col18.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col18);
-            //SCOPE_CATALOG
-            ColumnMetaData col19 = new ColumnMetaData();
-            col19.setColIndex(19);
-            col19.setColName("SCOPE_CATALOG");
-            col19.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col19);
-            //SCOPE_SCHEMA
-            ColumnMetaData col20 = new ColumnMetaData();
-            col20.setColIndex(20);
-            col20.setColName("SCOPE_SCHEMA");
-            col20.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col20);
-            //SCOPE_TABLE
-            ColumnMetaData col21 = new ColumnMetaData();
-            col21.setColIndex(21);
-            col21.setColName("SCOPE_TABLE");
-            col21.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col21);
-            //SOURCE_DATA_TYPE
-            ColumnMetaData col22 = new ColumnMetaData();
-            col22.setColIndex(22);
-            col22.setColName("SOURCE_DATA_TYPE");
-            col22.setColType(TSDBConstants.TSDB_DATA_TYPE_SMALLINT);
-            columnMetaDataList.add(col22);
-            //IS_AUTOINCREMENT
-            ColumnMetaData col23 = new ColumnMetaData();
-            col23.setColIndex(23);
-            col23.setColName("IS_AUTOINCREMENT");
-            col23.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col23);
-            //IS_GENERATEDCOLUMN
-            ColumnMetaData col24 = new ColumnMetaData();
-            col24.setColIndex(24);
-            col24.setColName("IS_GENERATEDCOLUMN");
-            col24.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col24);
-
-            resultSet.setColumnMetaDataList(columnMetaDataList);
-            // set up rowDataList
-            ResultSet rs = stmt.executeQuery("describe " + dbname + "." + tableNamePattern);
-            List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
-            int index = 0;
+        DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
+        // set up ColumnMetaDataList
+        resultSet.setColumnMetaDataList(buildGetColumnsColumnMetaDataList());
+        // set up rowDataList
+        List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("describe " + catalog + "." + tableNamePattern);
+            int rowIndex = 0;
             while (rs.next()) {
                 TSDBResultSetRowData rowData = new TSDBResultSetRowData(24);
                 // set TABLE_CAT
-                rowData.setString(0, dbname);
+                rowData.setStringValue(1, catalog);
+                // set TABLE_SCHEM
+                rowData.setStringValue(2, null);
                 // set TABLE_NAME
-                rowData.setString(2, tableNamePattern);
+                rowData.setStringValue(3, tableNamePattern);
                 // set COLUMN_NAME
-                rowData.setString(3, rs.getString("Field"));
+                rowData.setStringValue(4, rs.getString("Field"));
                 // set DATA_TYPE
                 String typeName = rs.getString("Type");
-                rowData.setInt(4, getDataType(typeName));
+                rowData.setIntValue(5, TSDBConstants.typeName2JdbcType(typeName));
                 // set TYPE_NAME
-                rowData.setString(5, typeName);
+                rowData.setStringValue(6, typeName);
                 // set COLUMN_SIZE
                 int length = rs.getInt("Length");
-                rowData.setInt(6, getColumnSize(typeName, length));
+                rowData.setIntValue(7, calculateColumnSize(typeName, precision, length));
+                // set BUFFER LENGTH
+                rowData.setStringValue(8, null);
                 // set DECIMAL_DIGITS
-                rowData.setInt(8, getDecimalDigits(typeName));
+                Integer decimalDigits = calculateDecimalDigits(typeName);
+                if (decimalDigits != null) {
+                    rowData.setIntValue(9, decimalDigits);
+                } else {
+                    rowData.setStringValue(9, null);
+                }
                 // set NUM_PREC_RADIX
-                rowData.setInt(9, 10);
+                rowData.setIntValue(10, 10);
                 // set NULLABLE
-                rowData.setInt(10, getNullable(index, typeName));
+                rowData.setIntValue(11, isNullable(rowIndex, typeName));
                 // set REMARKS
-                rowData.setString(11, rs.getString("Note"));
+                String note = rs.getString("Note");
+                rowData.setStringValue(12, note.trim().isEmpty() ? null : note);
                 rowDataList.add(rowData);
-                index++;
+                rowIndex++;
             }
             resultSet.setRowDataList(rowDataList);
-            return resultSet;
-
         } catch (SQLException e) {
             e.printStackTrace();
         }
-        return null;
+        return resultSet;
     }
 
-    protected int getNullable(int index, String typeName) {
+    private int isNullable(int index, String typeName) {
         if (index == 0 && "TIMESTAMP".equals(typeName))
             return DatabaseMetaData.columnNoNulls;
         return DatabaseMetaData.columnNullable;
     }
 
-    protected int getColumnSize(String typeName, int length) {
+    private Integer calculateColumnSize(String typeName, String precisionType, int length) {
         switch (typeName) {
             case "TIMESTAMP":
-                return 23;
-            default:
-                return 0;
-        }
-    }
-
-    protected int getDecimalDigits(String typeName) {
-        switch (typeName) {
+                return precisionType.equals("ms") ? TSDBConstants.TIMESTAMP_MS_PRECISION : TSDBConstants.TIMESTAMP_US_PRECISION;
+            case "BOOL":
+                return TSDBConstants.BOOLEAN_PRECISION;
+            case "TINYINT":
+                return TSDBConstants.TINYINT_PRECISION;
+            case "SMALLINT":
+                return TSDBConstants.SMALLINT_PRECISION;
+            case "INT":
+                return TSDBConstants.INT_PRECISION;
+            case "BIGINT":
+                return TSDBConstants.BIGINT_PRECISION;
             case "FLOAT":
-                return 5;
+                return TSDBConstants.FLOAT_PRECISION;
             case "DOUBLE":
-                return 9;
+                return TSDBConstants.DOUBLE_PRECISION;
+            case "NCHAR":
+            case "BINARY":
+                return length;
             default:
-                return 0;
+                return null;
         }
     }
 
-    protected int getDataType(String typeName) {
+    private Integer calculateDecimalDigits(String typeName) {
         switch (typeName) {
-            case "TIMESTAMP":
-                return Types.TIMESTAMP;
+            case "TINYINT":
+            case "SMALLINT":
             case "INT":
-                return Types.INTEGER;
             case "BIGINT":
-                return Types.BIGINT;
-            case "FLOAT":
-                return Types.FLOAT;
-            case "DOUBLE":
-                return Types.DOUBLE;
-            case "BINARY":
-                return Types.BINARY;
-            case "SMALLINT":
-                return Types.SMALLINT;
-            case "TINYINT":
-                return Types.TINYINT;
-            case "BOOL":
-                return Types.BOOLEAN;
-            case "NCHAR":
-                return Types.NCHAR;
+                return 0;
             default:
-                return Types.NULL;
+                return null;
         }
     }
 
-    public ResultSet getColumnPrivileges(String catalog, String schema, String table, String columnNamePattern)
-            throws SQLException {
+    private ColumnMetaData buildTableCatalogMeta(int colIndex) {
+        ColumnMetaData col1 = new ColumnMetaData();
+        col1.setColIndex(colIndex);
+        col1.setColName("TABLE_CAT");
+        col1.setColType(Types.NCHAR);
+        return col1;
+    }
+
+    private ColumnMetaData buildTableSchemaMeta(int colIndex) {
+        ColumnMetaData col2 = new ColumnMetaData();
+        col2.setColIndex(colIndex);
+        col2.setColName("TABLE_SCHEM");
+        col2.setColType(Types.NCHAR);
+        return col2;
+    }
+
+    private ColumnMetaData buildTableNameMeta(int colIndex) {
+        ColumnMetaData col3 = new ColumnMetaData();
+        col3.setColIndex(colIndex);
+        col3.setColName("TABLE_NAME");
+        col3.setColSize(193);
+        col3.setColType(Types.NCHAR);
+        return col3;
+    }
+
+    private ColumnMetaData buildColumnNameMeta(int colIndex) {
+        ColumnMetaData col4 = new ColumnMetaData();
+        col4.setColIndex(colIndex);
+        col4.setColName("COLUMN_NAME");
+        col4.setColSize(65);
+        col4.setColType(Types.NCHAR);
+        return col4;
+    }
+
+    private ColumnMetaData buildDataTypeMeta(int colIndex) {
+        ColumnMetaData col5 = new ColumnMetaData();
+        col5.setColIndex(colIndex);
+        col5.setColName("DATA_TYPE");
+        col5.setColType(Types.INTEGER);
+        return col5;
+    }
+
+    private ColumnMetaData buildColumnSizeMeta() {
+        ColumnMetaData col7 = new ColumnMetaData();
+        col7.setColIndex(7);
+        col7.setColName("COLUMN_SIZE");
+        col7.setColType(Types.INTEGER);
+        return col7;
+    }
+
+    private ColumnMetaData buildBufferLengthMeta() {
+        ColumnMetaData col8 = new ColumnMetaData();
+        col8.setColIndex(8);
+        col8.setColName("BUFFER_LENGTH");
+        return col8;
+    }
+
+    private ColumnMetaData buildDecimalDigitsMeta() {
+        ColumnMetaData col9 = new ColumnMetaData();
+        col9.setColIndex(9);
+        col9.setColName("DECIMAL_DIGITS");
+        col9.setColType(Types.INTEGER);
+        return col9;
+    }
+
+    private ColumnMetaData buildNumPrecRadixMeta() {
+        ColumnMetaData col10 = new ColumnMetaData();
+        col10.setColIndex(10);
+        col10.setColName("NUM_PREC_RADIX");
+        col10.setColType(Types.INTEGER);
+        return col10;
+    }
+
+    private ColumnMetaData buildNullableMeta() {
+        ColumnMetaData col11 = new ColumnMetaData();
+        col11.setColIndex(11);
+        col11.setColName("NULLABLE");
+        col11.setColType(Types.INTEGER);
+        return col11;
+    }
+
+    private ColumnMetaData buildRemarksMeta(int colIndex) {
+        ColumnMetaData col12 = new ColumnMetaData();
+        col12.setColIndex(colIndex);
+        col12.setColName("REMARKS");
+        col12.setColType(Types.NCHAR);
+        return col12;
+    }
+
+    private ColumnMetaData buildColumnDefMeta() {
+        ColumnMetaData col13 = new ColumnMetaData();
+        col13.setColIndex(13);
+        col13.setColName("COLUMN_DEF");
+        col13.setColType(Types.NCHAR);
+        return col13;
+    }
+
+    private ColumnMetaData buildSqlDataTypeMeta() {
+        ColumnMetaData col14 = new ColumnMetaData();
+        col14.setColIndex(14);
+        col14.setColName("SQL_DATA_TYPE");
+        col14.setColType(Types.INTEGER);
+        return col14;
+    }
+
+    private ColumnMetaData buildSqlDatetimeSubMeta() {
+        ColumnMetaData col15 = new ColumnMetaData();
+        col15.setColIndex(15);
+        col15.setColName("SQL_DATETIME_SUB");
+        col15.setColType(Types.INTEGER);
+        return col15;
+    }
+
+    private ColumnMetaData buildCharOctetLengthMeta() {
+        ColumnMetaData col16 = new ColumnMetaData();
+        col16.setColIndex(16);
+        col16.setColName("CHAR_OCTET_LENGTH");
+        col16.setColType(Types.INTEGER);
+        return col16;
+    }
+
+    private ColumnMetaData buildOrdinalPositionMeta() {
+        ColumnMetaData col17 = new ColumnMetaData();
+        col17.setColIndex(17);
+        col17.setColName("ORDINAL_POSITION");
+        col17.setColType(Types.INTEGER);
+        return col17;
+    }
+
+    private ColumnMetaData buildIsNullableMeta() {
+        ColumnMetaData col18 = new ColumnMetaData();
+        col18.setColIndex(18);
+        col18.setColName("IS_NULLABLE");
+        col18.setColType(Types.NCHAR);
+        return col18;
+    }
+
+    private ColumnMetaData buildScopeCatalogMeta() {
+        ColumnMetaData col19 = new ColumnMetaData();
+        col19.setColIndex(19);
+        col19.setColName("SCOPE_CATALOG");
+        col19.setColType(Types.NCHAR);
+        return col19;
+    }
+
+    private ColumnMetaData buildScopeSchemaMeta() {
+        ColumnMetaData col20 = new ColumnMetaData();
+        col20.setColIndex(20);
+        col20.setColName("SCOPE_SCHEMA");
+        col20.setColType(Types.NCHAR);
+        return col20;
+    }
+
+    private ColumnMetaData buildScopeTableMeta() {
+        ColumnMetaData col21 = new ColumnMetaData();
+        col21.setColIndex(21);
+        col21.setColName("SCOPE_TABLE");
+        col21.setColType(Types.NCHAR);
+        return col21;
+    }
+
+    private ColumnMetaData buildSourceDataTypeMeta() {
+        ColumnMetaData col22 = new ColumnMetaData();
+        col22.setColIndex(22);
+        col22.setColName("SOURCE_DATA_TYPE");
+        col22.setColType(TSDBConstants.TSDB_DATA_TYPE_SMALLINT);
+        return col22;
+    }
+
+    private ColumnMetaData buildIsAutoIncrementMeta() {
+        ColumnMetaData col23 = new ColumnMetaData();
+        col23.setColIndex(23);
+        col23.setColName("IS_AUTOINCREMENT");
+        col23.setColType(Types.NCHAR);
+        return col23;
+    }
+
+    private ColumnMetaData buildIsGeneratedColumnMeta() {
+        ColumnMetaData col24 = new ColumnMetaData();
+        col24.setColIndex(24);
+        col24.setColName("IS_GENERATEDCOLUMN");
+        col24.setColType(Types.NCHAR);
+        return col24;
+    }
+
+    private List<ColumnMetaData> buildGetColumnsColumnMetaDataList() {
+        List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
+        columnMetaDataList.add(buildTableCatalogMeta(1));        //1. TABLE_CAT
+        columnMetaDataList.add(buildTableSchemaMeta(2));         //2. TABLE_SCHEMA
+        columnMetaDataList.add(buildTableNameMeta(3));           //3. TABLE_NAME
+        columnMetaDataList.add(buildColumnNameMeta(4));          //4. COLUMN_NAME
+        columnMetaDataList.add(buildDataTypeMeta(5));            //5. DATA_TYPE
+        columnMetaDataList.add(buildTypeNameMeta(6));            //6. TYPE_NAME
+        columnMetaDataList.add(buildColumnSizeMeta());                    //7. COLUMN_SIZE
+        columnMetaDataList.add(buildBufferLengthMeta());                  //8. BUFFER_LENGTH, not used
+        columnMetaDataList.add(buildDecimalDigitsMeta());       //9. DECIMAL_DIGITS
+        columnMetaDataList.add(buildNumPrecRadixMeta());        //10. NUM_PREC_RADIX
+        columnMetaDataList.add(buildNullableMeta());            //11. NULLABLE
+        columnMetaDataList.add(buildRemarksMeta(12));  //12. REMARKS
+        columnMetaDataList.add(buildColumnDefMeta());           //13. COLUMN_DEF
+        columnMetaDataList.add(buildSqlDataTypeMeta());         //14. SQL_DATA_TYPE
+        columnMetaDataList.add(buildSqlDatetimeSubMeta());      //15. SQL_DATETIME_SUB
+        columnMetaDataList.add(buildCharOctetLengthMeta());     //16. CHAR_OCTET_LENGTH
+        columnMetaDataList.add(buildOrdinalPositionMeta());     //17. ORDINAL_POSITION
+        columnMetaDataList.add(buildIsNullableMeta());          //18. IS_NULLABLE
+        columnMetaDataList.add(buildScopeCatalogMeta());        //19. SCOPE_CATALOG
+        columnMetaDataList.add(buildScopeSchemaMeta());         //20. SCOPE_SCHEMA
+        columnMetaDataList.add(buildScopeTableMeta());          //21. SCOPE_TABLE
+        columnMetaDataList.add(buildSourceDataTypeMeta());      //22. SOURCE_DATA_TYPE
+        columnMetaDataList.add(buildIsAutoIncrementMeta());     //23. IS_AUTOINCREMENT
+        columnMetaDataList.add(buildIsGeneratedColumnMeta());   //24. IS_GENERATEDCOLUMN
+        return columnMetaDataList;
+    }
+
+    public ResultSet getColumnPrivileges(String catalog, String schema, String table, String columnNamePattern) throws SQLException {
         return getEmptyResultSet();
     }
 
-    public ResultSet getTablePrivileges(String catalog, String schemaPattern, String tableNamePattern)
-            throws SQLException {
+    public ResultSet getTablePrivileges(String catalog, String schemaPattern, String tableNamePattern) throws SQLException {
         return getEmptyResultSet();
     }
 
-    public ResultSet getBestRowIdentifier(String catalog, String schema, String table, int scope, boolean nullable)
-            throws SQLException {
+    public ResultSet getBestRowIdentifier(String catalog, String schema, String table, int scope, boolean nullable) throws SQLException {
         return getEmptyResultSet();
     }
 
@@ -914,8 +971,7 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
         return getEmptyResultSet();
     }
 
-    public ResultSet getCrossReference(String parentCatalog, String parentSchema, String parentTable,
-                                       String foreignCatalog, String foreignSchema, String foreignTable) throws SQLException {
+    public ResultSet getCrossReference(String parentCatalog, String parentSchema, String parentTable, String foreignCatalog, String foreignSchema, String foreignTable) throws SQLException {
         return getEmptyResultSet();
     }
 
@@ -923,8 +979,7 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
         return getEmptyResultSet();
     }
 
-    public ResultSet getIndexInfo(String catalog, String schema, String table, boolean unique, boolean approximate)
-            throws SQLException {
+    public ResultSet getIndexInfo(String catalog, String schema, String table, boolean unique, boolean approximate) throws SQLException {
         return getEmptyResultSet();
     }
 
@@ -976,8 +1031,7 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
         return false;
     }
 
-    public ResultSet getUDTs(String catalog, String schemaPattern, String typeNamePattern, int[] types)
-            throws SQLException {
+    public ResultSet getUDTs(String catalog, String schemaPattern, String typeNamePattern, int[] types) throws SQLException {
         return getEmptyResultSet();
     }
 
@@ -1005,8 +1059,7 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
 
     public abstract ResultSet getSuperTables(String catalog, String schemaPattern, String tableNamePattern) throws SQLException;
 
-    public ResultSet getAttributes(String catalog, String schemaPattern, String typeNamePattern,
-                                   String attributeNamePattern) throws SQLException {
+    public ResultSet getAttributes(String catalog, String schemaPattern, String typeNamePattern, String attributeNamePattern) throws SQLException {
         return getEmptyResultSet();
     }
 
@@ -1069,18 +1122,15 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
         return getEmptyResultSet();
     }
 
-    public ResultSet getFunctions(String catalog, String schemaPattern, String functionNamePattern)
-            throws SQLException {
+    public ResultSet getFunctions(String catalog, String schemaPattern, String functionNamePattern) throws SQLException {
         return getEmptyResultSet();
     }
 
-    public ResultSet getFunctionColumns(String catalog, String schemaPattern, String functionNamePattern,
-                                        String columnNamePattern) throws SQLException {
+    public ResultSet getFunctionColumns(String catalog, String schemaPattern, String functionNamePattern, String columnNamePattern) throws SQLException {
         return getEmptyResultSet();
     }
 
-    public ResultSet getPseudoColumns(String catalog, String schemaPattern, String tableNamePattern,
-                                      String columnNamePattern) throws SQLException {
+    public ResultSet getPseudoColumns(String catalog, String schemaPattern, String tableNamePattern, String columnNamePattern) throws SQLException {
         return getEmptyResultSet();
     }
 
@@ -1093,164 +1143,142 @@ public abstract class AbstractDatabaseMetaData extends WrapperImpl implements Da
     }
 
     protected ResultSet getCatalogs(Connection conn) throws SQLException {
-        try (Statement stmt = conn.createStatement()) {
-            DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
-            // set up ColumnMetaDataList
-            List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
-            // TABLE_CAT
-            ColumnMetaData col1 = new ColumnMetaData();
-            col1.setColIndex(1);
-            col1.setColName("TABLE_CAT");
-            col1.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col1);
-
-            resultSet.setColumnMetaDataList(columnMetaDataList);
+        DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
+        // set up ColumnMetaDataList
+        List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
+        columnMetaDataList.add(buildTableCatalogMeta(1));       // 1. TABLE_CAT
+        resultSet.setColumnMetaDataList(columnMetaDataList);
 
+        try (Statement stmt = conn.createStatement()) {
             List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
             ResultSet rs = stmt.executeQuery("show databases");
             while (rs.next()) {
                 TSDBResultSetRowData rowData = new TSDBResultSetRowData(1);
-                rowData.setString(0, rs.getString("name"));
+                rowData.setStringValue(1, rs.getString("name"));
                 rowDataList.add(rowData);
             }
             resultSet.setRowDataList(rowDataList);
-            return resultSet;
         }
+        return resultSet;
     }
 
 
     protected ResultSet getPrimaryKeys(String catalog, String schema, String table, Connection conn) throws SQLException {
-        try (Statement stmt = conn.createStatement()) {
-            if (catalog == null || catalog.isEmpty())
-                return null;
+        if (catalog == null || catalog.isEmpty())
+            return null;
+        if (!isAvailableCatalog(conn, catalog))
+            return new EmptyResultSet();
 
-            ResultSet databases = stmt.executeQuery("show databases");
-            String dbname = null;
-            while (databases.next()) {
-                dbname = databases.getString("name");
-                if (dbname.equalsIgnoreCase(catalog))
-                    break;
-            }
-            databases.close();
-            if (dbname == null)
-                return null;
-
-            stmt.execute("use " + dbname);
-            DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
+        DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
+        try (Statement stmt = conn.createStatement()) {
             // set up ColumnMetaDataList
-            List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
-            // TABLE_CAT
-            ColumnMetaData col1 = new ColumnMetaData();
-            col1.setColIndex(0);
-            col1.setColName("TABLE_CAT");
-            col1.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col1);
-            // TABLE_SCHEM
-            ColumnMetaData col2 = new ColumnMetaData();
-            col2.setColIndex(1);
-            col2.setColName("TABLE_SCHEM");
-            col2.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col2);
-            // TABLE_NAME
-            ColumnMetaData col3 = new ColumnMetaData();
-            col3.setColIndex(2);
-            col3.setColName("TABLE_NAME");
-            col3.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col3);
-            // COLUMN_NAME
-            ColumnMetaData col4 = new ColumnMetaData();
-            col4.setColIndex(3);
-            col4.setColName("COLUMN_NAME");
-            col4.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col4);
-            // KEY_SEQ
-            ColumnMetaData col5 = new ColumnMetaData();
-            col5.setColIndex(4);
-            col5.setColName("KEY_SEQ");
-            col5.setColType(TSDBConstants.TSDB_DATA_TYPE_INT);
-            columnMetaDataList.add(col5);
-            // PK_NAME
-            ColumnMetaData col6 = new ColumnMetaData();
-            col6.setColIndex(5);
-            col6.setColName("PK_NAME");
-            col6.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col6);
-            resultSet.setColumnMetaDataList(columnMetaDataList);
-
+            resultSet.setColumnMetaDataList(buildGetPrimaryKeysMetadataList());
             // set rowData
             List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
-            ResultSet rs = stmt.executeQuery("describe " + dbname + "." + table);
+            ResultSet rs = stmt.executeQuery("describe " + catalog + "." + table);
             rs.next();
             TSDBResultSetRowData rowData = new TSDBResultSetRowData(6);
-            rowData.setString(0, null);
-            rowData.setString(1, null);
-            rowData.setString(2, table);
-            String pkName = rs.getString(1);
-            rowData.setString(3, pkName);
-            rowData.setInt(4, 1);
-            rowData.setString(5, pkName);
+            rowData.setStringValue(1, catalog);
+            rowData.setStringValue(2, null);
+            rowData.setStringValue(3, table);
+            String primaryKey = rs.getString("Field");
+            rowData.setStringValue(4, primaryKey);
+            rowData.setShortValue(5, (short) 1);
+            rowData.setStringValue(6, primaryKey);
             rowDataList.add(rowData);
             resultSet.setRowDataList(rowDataList);
-            return resultSet;
         }
+        return resultSet;
     }
 
-    protected ResultSet getSuperTables(String catalog, String schemaPattern, String tableNamePattern, Connection conn) throws SQLException {
-        try (Statement stmt = conn.createStatement()) {
-            if (catalog == null || catalog.isEmpty())
-                return null;
+    private List<ColumnMetaData> buildGetPrimaryKeysMetadataList() {
+        List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
+        columnMetaDataList.add(buildTableCatalogMeta(1));   // 1. TABLE_CAT
+        columnMetaDataList.add(buildTableSchemaMeta(2));    // 2. TABLE_SCHEM
+        columnMetaDataList.add(buildTableNameMeta(3));      // 3. TABLE_NAME
+        columnMetaDataList.add(buildColumnNameMeta(4));     // 4. COLUMN_NAME
+        columnMetaDataList.add(buildKeySeqMeta(5));         // 5. KEY_SEQ
+        columnMetaDataList.add(buildPrimaryKeyNameMeta(6)); // 6. PK_NAME
+        return columnMetaDataList;
+    }
+
+    private ColumnMetaData buildKeySeqMeta(int colIndex) {
+        ColumnMetaData col5 = new ColumnMetaData();
+        col5.setColIndex(colIndex);
+        col5.setColName("KEY_SEQ");
+        col5.setColType(Types.SMALLINT);
+        return col5;
+    }
+
+    private ColumnMetaData buildPrimaryKeyNameMeta(int colIndex) {
+        ColumnMetaData col6 = new ColumnMetaData();
+        col6.setColIndex(colIndex);
+        col6.setColName("PK_NAME");
+        col6.setColType(Types.NCHAR);
+        return col6;
+    }
 
+    private boolean isAvailableCatalog(Connection connection, String catalog) {
+        try (Statement stmt = connection.createStatement()) {
             ResultSet databases = stmt.executeQuery("show databases");
-            String dbname = null;
             while (databases.next()) {
-                dbname = databases.getString("name");
+                String dbname = databases.getString("name");
+                this.database = dbname;
+                this.precision = databases.getString("precision");
                 if (dbname.equalsIgnoreCase(catalog))
-                    break;
+                    return true;
             }
             databases.close();
-            if (dbname == null)
-                return null;
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+        return false;
+    }
 
-            stmt.execute("use " + dbname);
-            DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
-            // set up ColumnMetaDataList
-            List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
-            // TABLE_CAT
-            ColumnMetaData col1 = new ColumnMetaData();
-            col1.setColIndex(0);
-            col1.setColName("TABLE_CAT");
-            col1.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col1);
-            // TABLE_SCHEM
-            ColumnMetaData col2 = new ColumnMetaData();
-            col2.setColIndex(1);
-            col2.setColName("TABLE_SCHEM");
-            col2.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col2);
-            // TABLE_NAME
-            ColumnMetaData col3 = new ColumnMetaData();
-            col3.setColIndex(2);
-            col3.setColName("TABLE_NAME");
-            col3.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col3);
-            // SUPERTABLE_NAME
-            ColumnMetaData col4 = new ColumnMetaData();
-            col4.setColIndex(3);
-            col4.setColName("SUPERTABLE_NAME");
-            col4.setColType(TSDBConstants.TSDB_DATA_TYPE_NCHAR);
-            columnMetaDataList.add(col4);
-            resultSet.setColumnMetaDataList(columnMetaDataList);
+    protected ResultSet getSuperTables(String catalog, String schemaPattern, String tableNamePattern, Connection conn) throws SQLException {
+        if (catalog == null || catalog.isEmpty())
+            return null;
+
+        if (!isAvailableCatalog(conn, catalog)) {
+            return new EmptyResultSet();
+        }
 
+        DatabaseMetaDataResultSet resultSet = new DatabaseMetaDataResultSet();
+        try (Statement stmt = conn.createStatement()) {
+            // set up ColumnMetaDataList
+            resultSet.setColumnMetaDataList(buildGetSuperTablesColumnMetaDataList());
+            // set result set row data
+            stmt.execute("use " + catalog);
             ResultSet rs = stmt.executeQuery("show tables like '" + tableNamePattern + "'");
             List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
             while (rs.next()) {
                 TSDBResultSetRowData rowData = new TSDBResultSetRowData(4);
-                rowData.setString(2, rs.getString(1));
-                rowData.setString(3, rs.getString(4));
+                rowData.setStringValue(1, catalog);
+                rowData.setStringValue(2, null);
+                rowData.setStringValue(3, rs.getString("table_name"));
+                rowData.setStringValue(4, rs.getString("stable_name"));
                 rowDataList.add(rowData);
             }
             resultSet.setRowDataList(rowDataList);
-            return resultSet;
         }
+        return resultSet;
+    }
+
+    private List<ColumnMetaData> buildGetSuperTablesColumnMetaDataList() {
+        List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
+        columnMetaDataList.add(buildTableCatalogMeta(1));       // 1. TABLE_CAT
+        columnMetaDataList.add(buildTableSchemaMeta(2));        // 2. TABLE_SCHEM
+        columnMetaDataList.add(buildTableNameMeta(3));          // 3. TABLE_NAME
+        columnMetaDataList.add(buildSuperTableNameMeta(4));     // 4. SUPERTABLE_NAME
+        return columnMetaDataList;
     }
+
+    private ColumnMetaData buildSuperTableNameMeta(int colIndex) {
+        ColumnMetaData col4 = new ColumnMetaData();
+        col4.setColIndex(colIndex);
+        col4.setColName("SUPERTABLE_NAME");
+        col4.setColType(Types.NCHAR);
+        return col4;
+    }
+
 }
\ No newline at end of file

src/connector/jdbc/src/main/java/com/taosdata/jdbc/AbstractParameterMetaData.java

 package com.taosdata.jdbc;
 
+import com.sun.org.apache.xpath.internal.operations.Bool;
+
 import java.sql.ParameterMetaData;
 import java.sql.SQLException;
 import java.sql.Timestamp;
@@ -49,6 +51,22 @@ public abstract class AbstractParameterMetaData extends WrapperImpl implements P
         if (param < 1 && param >= parameters.length)
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_PARAMETER_INDEX_OUT_RANGE);
 
+        if (parameters[param - 1] instanceof Boolean)
+            return TSDBConstants.BOOLEAN_PRECISION;
+        if (parameters[param - 1] instanceof Byte)
+            return TSDBConstants.TINYINT_PRECISION;
+        if (parameters[param - 1] instanceof Short)
+            return TSDBConstants.SMALLINT_PRECISION;
+        if (parameters[param - 1] instanceof Integer)
+            return TSDBConstants.INT_PRECISION;
+        if (parameters[param - 1] instanceof Long)
+            return TSDBConstants.BIGINT_PRECISION;
+        if (parameters[param - 1] instanceof Timestamp)
+            return TSDBConstants.TIMESTAMP_MS_PRECISION;
+        if (parameters[param - 1] instanceof Float)
+            return TSDBConstants.FLOAT_PRECISION;
+        if (parameters[param - 1] instanceof Double)
+            return TSDBConstants.DOUBLE_PRECISION;
         if (parameters[param - 1] instanceof String)
             return ((String) parameters[param - 1]).length();
         if (parameters[param - 1] instanceof byte[])
@@ -60,6 +78,11 @@ public abstract class AbstractParameterMetaData extends WrapperImpl implements P
     public int getScale(int param) throws SQLException {
         if (param < 1 && param >= parameters.length)
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_PARAMETER_INDEX_OUT_RANGE);
+
+        if (parameters[param - 1] instanceof Float)
+            return TSDBConstants.FLOAT_SCALE;
+        if (parameters[param - 1] instanceof Double)
+            return TSDBConstants.DOUBLE_SCALE;
         return 0;
     }
 

src/connector/jdbc/src/main/java/com/taosdata/jdbc/AbstractResultSet.java

@@ -66,10 +66,16 @@ public abstract class AbstractResultSet extends WrapperImpl implements ResultSet
     public abstract byte[] getBytes(int columnIndex) throws SQLException;
 
     @Override
-    public abstract Date getDate(int columnIndex) throws SQLException;
+    public Date getDate(int columnIndex) throws SQLException {
+        Timestamp timestamp = getTimestamp(columnIndex);
+        return timestamp == null ? null : new Date(timestamp.getTime());
+    }
 
     @Override
-    public abstract Time getTime(int columnIndex) throws SQLException;
+    public Time getTime(int columnIndex) throws SQLException {
+        Timestamp timestamp = getTimestamp(columnIndex);
+        return timestamp == null ? null : new Time(timestamp.getTime());
+    }
 
     @Override
     public abstract Timestamp getTimestamp(int columnIndex) throws SQLException;
@@ -84,10 +90,12 @@ public abstract class AbstractResultSet extends WrapperImpl implements ResultSet
     }
 
     @Override
+    @Deprecated
     public InputStream getUnicodeStream(int columnIndex) throws SQLException {
-        if (isClosed())
+        if (isClosed()) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_RESULTSET_CLOSED);
-
+        }
+        
         throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
     }
 
@@ -171,6 +179,7 @@ public abstract class AbstractResultSet extends WrapperImpl implements ResultSet
     }
 
     @Override
+    @Deprecated
     public InputStream getUnicodeStream(String columnLabel) throws SQLException {
         return getUnicodeStream(findColumn(columnLabel));
     }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/DatabaseMetaDataResultSet.java

@@ -14,76 +14,42 @@
  *****************************************************************************/
 package com.taosdata.jdbc;
 
-import java.io.InputStream;
-import java.io.Reader;
 import java.math.BigDecimal;
-import java.net.URL;
-import java.sql.Date;
 import java.sql.*;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Calendar;
+import java.util.Iterator;
+import java.util.List;
 
 /*
- * TDengine only supports a subset of the standard SQL, thus this implemetation of the
+ * TDengine only supports a subset of the standard SQL, thus this implementation of the
  * standard JDBC API contains more or less some adjustments customized for certain
  * compatibility needs.
  */
-public class DatabaseMetaDataResultSet implements ResultSet {
+public class DatabaseMetaDataResultSet extends AbstractResultSet {
 
-    private List<ColumnMetaData> columnMetaDataList;
-    private List<TSDBResultSetRowData> rowDataList;
+    private List<ColumnMetaData> columnMetaDataList = new ArrayList<>();
+    private List<TSDBResultSetRowData> rowDataList = new ArrayList<>();
     private TSDBResultSetRowData rowCursor;
 
     // position of cursor, starts from 0 as beforeFirst, increases as next() is called
     private int cursorRowNumber = 0;
 
-    public DatabaseMetaDataResultSet() {
-        rowDataList = new ArrayList<TSDBResultSetRowData>();
-        columnMetaDataList = new ArrayList<ColumnMetaData>();
-    }
-
-    public List<TSDBResultSetRowData> getRowDataList() {
-        return rowDataList;
-    }
-
     public void setRowDataList(List<TSDBResultSetRowData> rowDataList) {
         this.rowDataList = rowDataList;
     }
 
-    public List<ColumnMetaData> getColumnMetaDataList() {
-        return columnMetaDataList;
-    }
-
     public void setColumnMetaDataList(List<ColumnMetaData> columnMetaDataList) {
         this.columnMetaDataList = columnMetaDataList;
     }
 
-    public TSDBResultSetRowData getRowCursor() {
-        return rowCursor;
-    }
-
-    public void setRowCursor(TSDBResultSetRowData rowCursor) {
-        this.rowCursor = rowCursor;
-    }
-
     @Override
     public boolean next() throws SQLException {
-//        boolean ret = false;
-//        if (rowDataList.size() > 0) {
-//            ret = rowDataList.iterator().hasNext();
-//            if (ret) {
-//                rowCursor = rowDataList.iterator().next();
-//                cursorRowNumber++;
-//            }
-//        }
-//        return ret;
-
-        /**** add by zyyang 2020-09-29 ****************/
         boolean ret = false;
         if (!rowDataList.isEmpty() && cursorRowNumber < rowDataList.size()) {
             rowCursor = rowDataList.get(cursorRowNumber++);
             ret = true;
         }
-
         return ret;
     }
 
@@ -99,189 +65,72 @@ public class DatabaseMetaDataResultSet implements ResultSet {
 
     @Override
     public String getString(int columnIndex) throws SQLException {
-        columnIndex--;
-        int colType = columnMetaDataList.get(columnIndex).getColType();
-        return rowCursor.getString(columnIndex, colType);
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return rowCursor.getString(columnIndex, nativeType);
     }
 
     @Override
     public boolean getBoolean(int columnIndex) throws SQLException {
-        columnIndex--;
-        return rowCursor.getBoolean(columnIndex, columnMetaDataList.get(columnIndex).getColType());
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return rowCursor.getBoolean(columnIndex, nativeType);
     }
 
     @Override
     public byte getByte(int columnIndex) throws SQLException {
-        columnIndex--;
-        return (byte) rowCursor.getInt(columnIndex, columnMetaDataList.get(columnIndex).getColType());
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return (byte) rowCursor.getInt(columnIndex, nativeType);
     }
 
     @Override
     public short getShort(int columnIndex) throws SQLException {
-        columnIndex--;
-        return (short) rowCursor.getInt(columnIndex, columnMetaDataList.get(columnIndex).getColType());
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return (short) rowCursor.getInt(columnIndex, nativeType);
     }
 
     @Override
     public int getInt(int columnIndex) throws SQLException {
-        columnIndex--;
-        return rowCursor.getInt(columnIndex, columnMetaDataList.get(columnIndex).getColType());
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return rowCursor.getInt(columnIndex, nativeType);
     }
 
     @Override
     public long getLong(int columnIndex) throws SQLException {
-        columnIndex--;
-        return rowCursor.getLong(columnIndex, columnMetaDataList.get(columnIndex).getColType());
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return rowCursor.getLong(columnIndex, nativeType);
     }
 
     @Override
     public float getFloat(int columnIndex) throws SQLException {
-        columnIndex--;
-        return rowCursor.getFloat(columnIndex, columnMetaDataList.get(columnIndex).getColType());
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return rowCursor.getFloat(columnIndex, nativeType);
     }
 
     @Override
     public double getDouble(int columnIndex) throws SQLException {
-        columnIndex--;
-        return rowCursor.getDouble(columnIndex, columnMetaDataList.get(columnIndex).getColType());
-    }
-
-    @Override
-    public BigDecimal getBigDecimal(int columnIndex, int scale) throws SQLException {
-        columnIndex--;
-        return new BigDecimal(rowCursor.getDouble(columnIndex, columnMetaDataList.get(columnIndex).getColType()));
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return rowCursor.getDouble(columnIndex, nativeType);
     }
 
     @Override
     public byte[] getBytes(int columnIndex) throws SQLException {
-        columnIndex--;
-        return (rowCursor.getString(columnIndex, columnMetaDataList.get(columnIndex).getColType())).getBytes();
-    }
-
-    @Override
-    public Date getDate(int columnIndex) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public Time getTime(int columnIndex) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return (rowCursor.getString(columnIndex, nativeType)).getBytes();
     }
 
     @Override
     public Timestamp getTimestamp(int columnIndex) throws SQLException {
-        columnIndex--;
-        return rowCursor.getTimestamp(columnIndex);
-    }
-
-    @Override
-    public InputStream getAsciiStream(int columnIndex) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public InputStream getUnicodeStream(int columnIndex) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public InputStream getBinaryStream(int columnIndex) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public String getString(String columnLabel) throws SQLException {
-        return getString(findColumn(columnLabel));
-    }
-
-    @Override
-    public boolean getBoolean(String columnLabel) throws SQLException {
-        return getBoolean(findColumn(columnLabel));
-    }
-
-    @Override
-    public byte getByte(String columnLabel) throws SQLException {
-        return getByte(findColumn(columnLabel));
-    }
-
-    @Override
-    public short getShort(String columnLabel) throws SQLException {
-        return getShort(findColumn(columnLabel));
-    }
-
-    @Override
-    public int getInt(String columnLabel) throws SQLException {
-        return getInt(findColumn(columnLabel));
-    }
-
-    @Override
-    public long getLong(String columnLabel) throws SQLException {
-        return getLong(findColumn(columnLabel));
-    }
-
-    @Override
-    public float getFloat(String columnLabel) throws SQLException {
-        return getFloat(findColumn(columnLabel));
-    }
-
-    @Override
-    public double getDouble(String columnLabel) throws SQLException {
-        return getDouble(findColumn(columnLabel));
-    }
-
-    @Override
-    public BigDecimal getBigDecimal(String columnLabel, int scale) throws SQLException {
-        return getBigDecimal(findColumn(columnLabel));
-    }
-
-    @Override
-    public byte[] getBytes(String columnLabel) throws SQLException {
-        return getBytes(findColumn(columnLabel));
-    }
-
-    @Override
-    public Date getDate(String columnLabel) throws SQLException {
-        return getDate(findColumn(columnLabel));
-    }
-
-    @Override
-    public Time getTime(String columnLabel) throws SQLException {
-        return getTime(findColumn(columnLabel));
-    }
-
-    @Override
-    public Timestamp getTimestamp(String columnLabel) throws SQLException {
-        return getTimestamp(findColumn(columnLabel));
-    }
-
-    @Override
-    public InputStream getAsciiStream(String columnLabel) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public InputStream getUnicodeStream(String columnLabel) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public InputStream getBinaryStream(String columnLabel) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public SQLWarning getWarnings() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void clearWarnings() throws SQLException {
-
-    }
-
-    @Override
-    public String getCursorName() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        return rowCursor.getTimestamp(columnIndex,nativeType);
     }
 
     @Override
@@ -291,12 +140,7 @@ public class DatabaseMetaDataResultSet implements ResultSet {
 
     @Override
     public Object getObject(int columnIndex) throws SQLException {
-        return rowCursor.get(columnIndex);
-    }
-
-    @Override
-    public Object getObject(String columnLabel) throws SQLException {
-        return rowCursor.get(findColumn(columnLabel));
+        return rowCursor.getObject(columnIndex);
     }
 
     @Override
@@ -304,31 +148,19 @@ public class DatabaseMetaDataResultSet implements ResultSet {
         Iterator<ColumnMetaData> colMetaDataIt = this.columnMetaDataList.iterator();
         while (colMetaDataIt.hasNext()) {
             ColumnMetaData colMetaData = colMetaDataIt.next();
-            if (colMetaData.getColName() != null && colMetaData.getColName().equalsIgnoreCase(columnLabel)) {
-                return colMetaData.getColIndex() + 1;
+            if (colMetaData.getColName() != null && colMetaData.getColName().equals(columnLabel)) {
+                return colMetaData.getColIndex();
             }
         }
         throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_INVALID_VARIABLE);
     }
 
-    @Override
-    public Reader getCharacterStream(int columnIndex) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public Reader getCharacterStream(String columnLabel) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
     @Override
     public BigDecimal getBigDecimal(int columnIndex) throws SQLException {
-        return new BigDecimal(rowCursor.getDouble(columnIndex, columnMetaDataList.get(columnIndex).getColType()));
-    }
-
-    @Override
-    public BigDecimal getBigDecimal(String columnLabel) throws SQLException {
-        return getBigDecimal(findColumn(columnLabel));
+        int colType = columnMetaDataList.get(columnIndex - 1).getColType();
+        int nativeType = TSDBConstants.jdbcType2TaosType(colType);
+        double value = rowCursor.getDouble(columnIndex, nativeType);
+        return new BigDecimal(value);
     }
 
     @Override
@@ -378,7 +210,6 @@ public class DatabaseMetaDataResultSet implements ResultSet {
         } else {
             return 0;
         }
-
     }
 
     @Override
@@ -397,680 +228,23 @@ public class DatabaseMetaDataResultSet implements ResultSet {
     }
 
     @Override
-    public void setFetchDirection(int direction) throws SQLException {
-
-    }
-
-    @Override
-    public int getFetchDirection() throws SQLException {
-        return ResultSet.FETCH_FORWARD;
-    }
-
-    @Override
-    public void setFetchSize(int rows) throws SQLException {
-
-    }
-
-    @Override
-    public int getFetchSize() throws SQLException {
-        return 0;
-    }
-
-    @Override
-    public int getType() throws SQLException {
-        return ResultSet.TYPE_FORWARD_ONLY;
-    }
-
-    @Override
-    public int getConcurrency() throws SQLException {
-        return ResultSet.CONCUR_READ_ONLY;
-    }
-
-    @Override
-    public boolean rowUpdated() throws SQLException {
-        return false;
+    public Statement getStatement() throws SQLException {
+        return null;
     }
 
-    @Override
-    public boolean rowInserted() throws SQLException {
-        return false;
+    public Timestamp getTimestamp(int columnIndex, Calendar cal) throws SQLException {
+        //TODO: calendar is not used
+        return getTimestamp(columnIndex);
     }
 
     @Override
-    public boolean rowDeleted() throws SQLException {
+    public boolean isClosed() throws SQLException {
         return false;
     }
 
     @Override
-    public void updateNull(int columnIndex) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateBoolean(int columnIndex, boolean x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateByte(int columnIndex, byte x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateShort(int columnIndex, short x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateInt(int columnIndex, int x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateLong(int columnIndex, long x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateFloat(int columnIndex, float x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateDouble(int columnIndex, double x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateBigDecimal(int columnIndex, BigDecimal x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateString(int columnIndex, String x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateBytes(int columnIndex, byte[] x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateDate(int columnIndex, Date x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateTime(int columnIndex, Time x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateTimestamp(int columnIndex, Timestamp x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateAsciiStream(int columnIndex, InputStream x, int length) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateBinaryStream(int columnIndex, InputStream x, int length) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateCharacterStream(int columnIndex, Reader x, int length) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateObject(int columnIndex, Object x, int scaleOrLength) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateObject(int columnIndex, Object x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateNull(String columnLabel) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateBoolean(String columnLabel, boolean x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateByte(String columnLabel, byte x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateShort(String columnLabel, short x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateInt(String columnLabel, int x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateLong(String columnLabel, long x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateFloat(String columnLabel, float x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateDouble(String columnLabel, double x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateBigDecimal(String columnLabel, BigDecimal x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateString(String columnLabel, String x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
+    public String getNString(int columnIndex) throws SQLException {
+        return getString(columnIndex);
     }
 
-    @Override
-    public void updateBytes(String columnLabel, byte[] x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateDate(String columnLabel, Date x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateTime(String columnLabel, Time x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateTimestamp(String columnLabel, Timestamp x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateAsciiStream(String columnLabel, InputStream x, int length) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateBinaryStream(String columnLabel, InputStream x, int length) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateCharacterStream(String columnLabel, Reader reader, int length) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateObject(String columnLabel, Object x, int scaleOrLength) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateObject(String columnLabel, Object x) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void insertRow() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void updateRow() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void deleteRow() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void refreshRow() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void cancelRowUpdates() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void moveToInsertRow() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public void moveToCurrentRow() throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public Statement getStatement() throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Object getObject(int columnIndex, Map<String, Class<?>> map) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public Ref getRef(int columnIndex) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public Blob getBlob(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Clob getClob(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Array getArray(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Object getObject(String columnLabel, Map<String, Class<?>> map) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Ref getRef(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Blob getBlob(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Clob getClob(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Array getArray(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Date getDate(int columnIndex, Calendar cal) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Date getDate(String columnLabel, Calendar cal) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Time getTime(int columnIndex, Calendar cal) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Time getTime(String columnLabel, Calendar cal) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Timestamp getTimestamp(int columnIndex, Calendar cal) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Timestamp getTimestamp(String columnLabel, Calendar cal) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public URL getURL(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public URL getURL(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public void updateRef(int columnIndex, Ref x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateRef(String columnLabel, Ref x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBlob(int columnIndex, Blob x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBlob(String columnLabel, Blob x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateClob(int columnIndex, Clob x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateClob(String columnLabel, Clob x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateArray(int columnIndex, Array x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateArray(String columnLabel, Array x) throws SQLException {
-
-    }
-
-    @Override
-    public RowId getRowId(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public RowId getRowId(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public void updateRowId(int columnIndex, RowId x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateRowId(String columnLabel, RowId x) throws SQLException {
-
-    }
-
-    @Override
-    public int getHoldability() throws SQLException {
-        return 0;
-    }
-
-    @Override
-    public boolean isClosed() throws SQLException {
-        return false;
-    }
-
-    @Override
-    public void updateNString(int columnIndex, String nString) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNString(String columnLabel, String nString) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNClob(int columnIndex, NClob nClob) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNClob(String columnLabel, NClob nClob) throws SQLException {
-
-    }
-
-    @Override
-    public NClob getNClob(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public NClob getNClob(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public SQLXML getSQLXML(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public SQLXML getSQLXML(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public void updateSQLXML(int columnIndex, SQLXML xmlObject) throws SQLException {
-
-    }
-
-    @Override
-    public void updateSQLXML(String columnLabel, SQLXML xmlObject) throws SQLException {
-
-    }
-
-    @Override
-    public String getNString(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public String getNString(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Reader getNCharacterStream(int columnIndex) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public Reader getNCharacterStream(String columnLabel) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public void updateNCharacterStream(int columnIndex, Reader x, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNCharacterStream(String columnLabel, Reader reader, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateAsciiStream(int columnIndex, InputStream x, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBinaryStream(int columnIndex, InputStream x, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateCharacterStream(int columnIndex, Reader x, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateAsciiStream(String columnLabel, InputStream x, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBinaryStream(String columnLabel, InputStream x, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateCharacterStream(String columnLabel, Reader reader, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBlob(int columnIndex, InputStream inputStream, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBlob(String columnLabel, InputStream inputStream, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateClob(int columnIndex, Reader reader, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateClob(String columnLabel, Reader reader, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNClob(int columnIndex, Reader reader, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNClob(String columnLabel, Reader reader, long length) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNCharacterStream(int columnIndex, Reader x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNCharacterStream(String columnLabel, Reader reader) throws SQLException {
-
-    }
-
-    @Override
-    public void updateAsciiStream(int columnIndex, InputStream x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBinaryStream(int columnIndex, InputStream x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateCharacterStream(int columnIndex, Reader x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateAsciiStream(String columnLabel, InputStream x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBinaryStream(String columnLabel, InputStream x) throws SQLException {
-
-    }
-
-    @Override
-    public void updateCharacterStream(String columnLabel, Reader reader) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBlob(int columnIndex, InputStream inputStream) throws SQLException {
-
-    }
-
-    @Override
-    public void updateBlob(String columnLabel, InputStream inputStream) throws SQLException {
-
-    }
-
-    @Override
-    public void updateClob(int columnIndex, Reader reader) throws SQLException {
-
-    }
-
-    @Override
-    public void updateClob(String columnLabel, Reader reader) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNClob(int columnIndex, Reader reader) throws SQLException {
-
-    }
-
-    @Override
-    public void updateNClob(String columnLabel, Reader reader) throws SQLException {
-
-    }
-
-    @Override
-    public <T> T getObject(int columnIndex, Class<T> type) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public <T> T getObject(String columnLabel, Class<T> type) throws SQLException {
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-    }
-
-    @Override
-    public <T> T unwrap(Class<T> iface) throws SQLException {
-        return null;
-    }
-
-    @Override
-    public boolean isWrapperFor(Class<?> iface) throws SQLException {
-        return false;
-    }
-
-    private int getTrueColumnIndex(int columnIndex) throws SQLException {
-        if (columnIndex < 1) {
-            throw new SQLException("Column Index out of range, " + columnIndex + " < " + 1);
-        }
-
-        int numOfCols = this.columnMetaDataList.size();
-        if (columnIndex > numOfCols) {
-            throw new SQLException("Column Index out of range, " + columnIndex + " > " + numOfCols);
-        }
-
-        return columnIndex - 1;
-    }
 }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBConnection.java

@@ -49,7 +49,7 @@ public class TSDBConnection extends AbstractConnection {
         this.databaseMetaData.setConnection(this);
     }
 
-    public TSDBJNIConnector getConnection() {
+    public TSDBJNIConnector getConnector() {
         return this.connector;
     }
 
@@ -58,7 +58,7 @@ public class TSDBConnection extends AbstractConnection {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_CONNECTION_CLOSED);
         }
 
-        return new TSDBStatement(this, this.connector);
+        return new TSDBStatement(this);
     }
 
     public TSDBSubscribe subscribe(String topic, String sql, boolean restart) throws SQLException {
@@ -74,14 +74,18 @@ public class TSDBConnection extends AbstractConnection {
     }
 
     public PreparedStatement prepareStatement(String sql) throws SQLException {
-        if (isClosed())
+        if (isClosed()) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_CONNECTION_CLOSED);
-        return new TSDBPreparedStatement(this, this.connector, sql);
+        }
+        
+        return new TSDBPreparedStatement(this, sql);
     }
 
     public void close() throws SQLException {
-        if (isClosed)
+        if (isClosed) {
             return;
+        }
+        
         this.connector.closeConnection();
         this.isClosed = true;
     }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBConstants.java

@@ -41,15 +41,15 @@ public abstract class TSDBConstants {
     public static final int TSDB_DATA_TYPE_BINARY = 8;
     public static final int TSDB_DATA_TYPE_TIMESTAMP = 9;
     public static final int TSDB_DATA_TYPE_NCHAR = 10;
-    /*
-    系统增加新的无符号数据类型，分别是：
-        unsigned tinyint， 数值范围：0-254, NULL 为255
-        unsigned smallint，数值范围： 0-65534， NULL 为65535
-        unsigned int，数值范围：0-4294967294，NULL 为4294967295u
-        unsigned bigint，数值范围：0-18446744073709551614u，NULL 为18446744073709551615u。
-    example:
-        create table tb(ts timestamp, a tinyint unsigned, b smallint unsigned, c int unsigned, d bigint unsigned);
-    */
+    /**
+     * 系统增加新的无符号数据类型，分别是：
+     * unsigned tinyint， 数值范围：0-254, NULL 为255
+     * unsigned smallint，数值范围： 0-65534， NULL 为65535
+     * unsigned int，数值范围：0-4294967294，NULL 为4294967295u
+     * unsigned bigint，数值范围：0-18446744073709551614u，NULL 为18446744073709551615u。
+     * example:
+     * create table tb(ts timestamp, a tinyint unsigned, b smallint unsigned, c int unsigned, d bigint unsigned);
+     */
     public static final int TSDB_DATA_TYPE_UTINYINT = 11;       //unsigned tinyint
     public static final int TSDB_DATA_TYPE_USMALLINT = 12;      //unsigned smallint
     public static final int TSDB_DATA_TYPE_UINT = 13;           //unsigned int
@@ -57,6 +57,47 @@ public abstract class TSDBConstants {
     // nchar column max length
     public static final int maxFieldSize = 16 * 1024;
 
+    // precision for data types
+    public static final int BOOLEAN_PRECISION = 1;
+    public static final int TINYINT_PRECISION = 4;
+    public static final int SMALLINT_PRECISION = 6;
+    public static final int INT_PRECISION = 11;
+    public static final int BIGINT_PRECISION = 20;
+    public static final int FLOAT_PRECISION = 12;
+    public static final int DOUBLE_PRECISION = 22;
+    public static final int TIMESTAMP_MS_PRECISION = 23;
+    public static final int TIMESTAMP_US_PRECISION = 26;
+    // scale for data types
+    public static final int FLOAT_SCALE = 31;
+    public static final int DOUBLE_SCALE = 31;
+
+    public static int typeName2JdbcType(String type) {
+        switch (type.toUpperCase()) {
+            case "TIMESTAMP":
+                return Types.TIMESTAMP;
+            case "INT":
+                return Types.INTEGER;
+            case "BIGINT":
+                return Types.BIGINT;
+            case "FLOAT":
+                return Types.FLOAT;
+            case "DOUBLE":
+                return Types.DOUBLE;
+            case "BINARY":
+                return Types.BINARY;
+            case "SMALLINT":
+                return Types.SMALLINT;
+            case "TINYINT":
+                return Types.TINYINT;
+            case "BOOL":
+                return Types.BOOLEAN;
+            case "NCHAR":
+                return Types.NCHAR;
+            default:
+                return Types.NULL;
+        }
+    }
+
     public static int taosType2JdbcType(int taosType) throws SQLException {
         switch (taosType) {
             case TSDBConstants.TSDB_DATA_TYPE_BOOL:
@@ -88,7 +129,7 @@ public abstract class TSDBConstants {
     }
 
     public static String taosType2JdbcTypeName(int taosType) throws SQLException {
-        switch (taosType){
+        switch (taosType) {
             case TSDBConstants.TSDB_DATA_TYPE_BOOL:
                 return "BOOL";
             case TSDBConstants.TSDB_DATA_TYPE_UTINYINT:
@@ -119,7 +160,7 @@ public abstract class TSDBConstants {
     }
 
     public static int jdbcType2TaosType(int jdbcType) throws SQLException {
-        switch (jdbcType){
+        switch (jdbcType) {
             case Types.BOOLEAN:
                 return TSDBConstants.TSDB_DATA_TYPE_BOOL;
             case Types.TINYINT:
@@ -145,7 +186,7 @@ public abstract class TSDBConstants {
     }
 
     public static String jdbcType2TaosTypeName(int jdbcType) throws SQLException {
-        switch (jdbcType){
+        switch (jdbcType) {
             case Types.BOOLEAN:
                 return "BOOL";
             case Types.TINYINT:

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBJNIConnector.java

@@ -18,6 +18,7 @@ package com.taosdata.jdbc;
 
 import com.taosdata.jdbc.utils.TaosInfo;
 
+import java.nio.ByteBuffer;
 import java.sql.SQLException;
 import java.sql.SQLWarning;
 import java.util.List;
@@ -29,10 +30,13 @@ public class TSDBJNIConnector {
     private static volatile Boolean isInitialized = false;
 
     private TaosInfo taosInfo = TaosInfo.getInstance();
+
     // Connection pointer used in C
     private long taos = TSDBConstants.JNI_NULL_POINTER;
+
     // result set status in current connection
     private boolean isResultsetClosed;
+
     private int affectedRows = -1;
 
     static {
@@ -75,7 +79,6 @@ public class TSDBJNIConnector {
 
     public boolean connect(String host, int port, String dbName, String user, String password) throws SQLException {
         if (this.taos != TSDBConstants.JNI_NULL_POINTER) {
-//            this.closeConnectionImp(this.taos);
             closeConnection();
             this.taos = TSDBConstants.JNI_NULL_POINTER;
         }
@@ -97,12 +100,6 @@ public class TSDBJNIConnector {
      * @throws SQLException
      */
     public long executeQuery(String sql) throws SQLException {
-        // close previous result set if the user forgets to invoke the
-        // free method to close previous result set.
-//        if (!this.isResultsetClosed) {
-//            freeResultSet(taosResultSetPointer);
-//        }
-
         Long pSql = 0l;
         try {
             pSql = this.executeQueryImp(sql.getBytes(TaosGlobalConfig.getCharset()), this.taos);
@@ -170,7 +167,7 @@ public class TSDBJNIConnector {
     private native long isUpdateQueryImp(long connection, long pSql);
 
     /**
-     * Free resultset operation from C to release resultset pointer by JNI
+     * Free result set operation from C to release result set pointer by JNI
      */
     public int freeResultSet(long pSql) {
         int res = this.freeResultSetImp(this.taos, pSql);
@@ -178,19 +175,6 @@ public class TSDBJNIConnector {
         return res;
     }
 
-    /**
-     * Close the open result set which is associated to the current connection. If the result set is already
-     * closed, return 0 for success.
-     */
-//    public int freeResultSet() {
-//        int resCode = TSDBConstants.JNI_SUCCESS;
-//        if (!isResultsetClosed) {
-//            resCode = this.freeResultSetImp(this.taos, this.taosResultSetPointer);
-//            taosResultSetPointer = TSDBConstants.JNI_NULL_POINTER;
-//            isResultsetClosed = true;
-//        }
-//        return resCode;
-//    }
     private native int freeResultSetImp(long connection, long result);
 
     /**
@@ -210,7 +194,9 @@ public class TSDBJNIConnector {
      * Get schema metadata
      */
     public int getSchemaMetaData(long resultSet, List<ColumnMetaData> columnMetaData) {
-        return this.getSchemaMetaDataImp(this.taos, resultSet, columnMetaData);
+        int ret = this.getSchemaMetaDataImp(this.taos, resultSet, columnMetaData);
+        columnMetaData.stream().forEach(column -> column.setColIndex(column.getColIndex() + 1));
+        return ret;
     }
 
     private native int getSchemaMetaDataImp(long connection, long resultSet, List<ColumnMetaData> columnMetaData);
@@ -237,6 +223,7 @@ public class TSDBJNIConnector {
      */
     public void closeConnection() throws SQLException {
         int code = this.closeConnectionImp(this.taos);
+
         if (code < 0) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_JNI_CONNECTION_NULL);
         } else if (code == 0) {
@@ -244,6 +231,7 @@ public class TSDBJNIConnector {
         } else {
             throw new SQLException("Undefined error code returned by TDengine when closing a connection");
         }
+
         // invoke closeConnectionImpl only here
         taosInfo.connect_close_increment();
     }
@@ -280,7 +268,7 @@ public class TSDBJNIConnector {
     private native void unsubscribeImp(long subscription, boolean isKeep);
 
     /**
-     * Validate if a <I>create table</I> sql statement is correct without actually creating that table
+     * Validate if a <I>create table</I> SQL statement is correct without actually creating that table
      */
     public boolean validateCreateTableSql(String sql) {
         int res = validateCreateTableSqlImp(taos, sql.getBytes());
@@ -288,4 +276,76 @@ public class TSDBJNIConnector {
     }
 
     private native int validateCreateTableSqlImp(long connection, byte[] sqlBytes);
+
+    public long prepareStmt(String sql) throws SQLException {
+        Long stmt;
+        try {
+            stmt = prepareStmtImp(sql.getBytes(), this.taos);
+        } catch (Exception e) {
+            e.printStackTrace();
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_ENCODING);
+        }
+
+        if (stmt == TSDBConstants.JNI_CONNECTION_NULL) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_JNI_CONNECTION_NULL);
+        }
+
+        if (stmt == TSDBConstants.JNI_SQL_NULL) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_JNI_SQL_NULL);
+        }
+
+        if (stmt == TSDBConstants.JNI_OUT_OF_MEMORY) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_JNI_OUT_OF_MEMORY);
+        }
+
+        return stmt;
+    }
+
+    private native long prepareStmtImp(byte[] sql, long con);
+
+    public void setBindTableName(long stmt, String tableName) throws SQLException {
+        int code = setBindTableNameImp(stmt, tableName, this.taos);
+        if (code != TSDBConstants.JNI_SUCCESS) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "failed to set table name");
+        }
+    }
+
+    private native int setBindTableNameImp(long stmt, String name, long conn);
+
+    public void setBindTableNameAndTags(long stmt, String tableName, int numOfTags, ByteBuffer tags, ByteBuffer typeList, ByteBuffer lengthList, ByteBuffer nullList) throws SQLException {
+        int code = setTableNameTagsImp(stmt, tableName, numOfTags, tags.array(), typeList.array(), lengthList.array(),
+                nullList.array(), this.taos);
+        if (code != TSDBConstants.JNI_SUCCESS) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "failed to bind table name and corresponding tags");
+        }
+    }
+
+    private native int setTableNameTagsImp(long stmt, String name, int numOfTags, byte[] tags, byte[] typeList, byte[] lengthList, byte[] nullList, long conn);
+
+    public void bindColumnDataArray(long stmt, ByteBuffer colDataList, ByteBuffer lengthList, ByteBuffer isNullList, int type, int bytes, int numOfRows, int columnIndex) throws SQLException {
+        int code = bindColDataImp(stmt, colDataList.array(), lengthList.array(), isNullList.array(), type, bytes, numOfRows, columnIndex, this.taos);
+        if (code != TSDBConstants.JNI_SUCCESS) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "failed to bind column data");
+        }
+    }
+
+    private native int bindColDataImp(long stmt, byte[] colDataList, byte[] lengthList, byte[] isNullList, int type, int bytes, int numOfRows, int columnIndex, long conn);
+
+    public void executeBatch(long stmt) throws SQLException {
+        int code = executeBatchImp(stmt, this.taos);
+        if (code != TSDBConstants.JNI_SUCCESS) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "failed to execute batch bind");
+        }
+    }
+
+    private native int executeBatchImp(long stmt, long con);
+
+    public void closeBatch(long stmt) throws SQLException {
+        int code = closeStmt(stmt, this.taos);
+        if (code != TSDBConstants.JNI_SUCCESS) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "failed to close batch bind");
+        }
+    }
+
+    private native int closeStmt(long stmt, long con);
 }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBPreparedStatement.java

@@ -18,33 +18,43 @@ import com.taosdata.jdbc.utils.Utils;
 
 import java.io.InputStream;
 import java.io.Reader;
+import java.io.UnsupportedEncodingException;
 import java.math.BigDecimal;
 import java.net.URL;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
 import java.sql.*;
 import java.util.ArrayList;
 import java.util.Calendar;
+import java.util.Collections;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 /*
- * TDengine only supports a subset of the standard SQL, thus this implemetation of the
+ * TDengine only supports a subset of the standard SQL, thus this implementation of the
  * standard JDBC API contains more or less some adjustments customized for certain
  * compatibility needs.
  */
 public class TSDBPreparedStatement extends TSDBStatement implements PreparedStatement {
-
     private String rawSql;
     private Object[] parameters;
     private boolean isPrepared;
 
+    private ArrayList<ColumnInfo> colData;
+    private ArrayList<TableTagInfo> tableTags;
+    private int tagValueLength;
+
+    private String tableName;
+    private long nativeStmtHandle = 0;
+
     private volatile TSDBParameterMetaData parameterMetaData;
 
-    TSDBPreparedStatement(TSDBConnection connection, TSDBJNIConnector connecter, String sql) {
-        super(connection, connecter);
+    TSDBPreparedStatement(TSDBConnection connection, String sql) {
+        super(connection);
         init(sql);
 
+        int parameterCnt = 0;
         if (sql.contains("?")) {
-            int parameterCnt = 0;
             for (int i = 0; i < sql.length(); i++) {
                 if ('?' == sql.charAt(i)) {
                     parameterCnt++;
@@ -53,6 +63,12 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
             parameters = new Object[parameterCnt];
             this.isPrepared = true;
         }
+
+        if (parameterCnt > 1) {
+            // the table name is also a parameter, so ignore it.
+            this.colData = new ArrayList<ColumnInfo>();
+            this.tableTags = new ArrayList<TableTagInfo>();
+        }
     }
 
     private void init(String sql) {
@@ -189,9 +205,7 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
 
     @Override
     public void setBigDecimal(int parameterIndex, BigDecimal x) throws SQLException {
-        if (isClosed())
-            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
+        setObject(parameterIndex, x.doubleValue());
     }
 
     @Override
@@ -206,16 +220,12 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
 
     @Override
     public void setDate(int parameterIndex, Date x) throws SQLException {
-        if (isClosed())
-            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
+        setObject(parameterIndex, new Timestamp(x.getTime()));
     }
 
     @Override
     public void setTime(int parameterIndex, Time x) throws SQLException {
-        if (isClosed())
-            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
+        setObject(parameterIndex, new Timestamp(x.getTime()));
     }
 
     @Override
@@ -260,10 +270,13 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
 
     @Override
     public void setObject(int parameterIndex, Object x) throws SQLException {
-        if (isClosed())
+        if (isClosed()) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-        if (parameterIndex < 1 && parameterIndex >= parameters.length)
+        }
+
+        if (parameterIndex < 1 && parameterIndex >= parameters.length) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_PARAMETER_INDEX_OUT_RANGE);
+        }
         parameters[parameterIndex - 1] = x;
     }
 
@@ -300,8 +313,9 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
 
     @Override
     public void setRef(int parameterIndex, Ref x) throws SQLException {
-        if (isClosed())
+        if (isClosed()) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
+        }
 
         throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
     }
@@ -329,9 +343,9 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
 
     @Override
     public ResultSetMetaData getMetaData() throws SQLException {
-        if (isClosed())
-            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
+        if (this.getResultSet() == null)
+            return null;
+        return getResultSet().getMetaData();
     }
 
     @Override
@@ -375,10 +389,7 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
         if (isClosed())
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
 
-        if (parameterMetaData == null) {
-            this.parameterMetaData = new TSDBParameterMetaData(parameters);
-        }
-        return this.parameterMetaData;
+        return new TSDBParameterMetaData(parameters);
     }
 
     @Override
@@ -390,9 +401,7 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
 
     @Override
     public void setNString(int parameterIndex, String value) throws SQLException {
-        if (isClosed())
-            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
+        setString(parameterIndex, value);
     }
 
     @Override
@@ -515,4 +524,495 @@ public class TSDBPreparedStatement extends TSDBStatement implements PreparedStat
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
         throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
     }
+
+    ///////////////////////////////////////////////////////////////////////
+    // NOTE: the following APIs are not JDBC compatible
+    // set the bind table name
+    private static class ColumnInfo {
+        @SuppressWarnings("rawtypes")
+        private ArrayList data;
+        private int type;
+        private int bytes;
+        private boolean typeIsSet;
+
+        public ColumnInfo() {
+            this.typeIsSet = false;
+        }
+
+        public void setType(int type) throws SQLException {
+            if (this.isTypeSet()) {
+                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "column data type has been set");
+            }
+
+            this.typeIsSet = true;
+            this.type = type;
+        }
+
+        public boolean isTypeSet() {
+            return this.typeIsSet;
+        }
+    }
+
+    ;
+
+    private static class TableTagInfo {
+        private boolean isNull;
+        private Object value;
+        private int type;
+
+        public TableTagInfo(Object value, int type) {
+            this.value = value;
+            this.type = type;
+        }
+
+        public static TableTagInfo createNullTag(int type) {
+            TableTagInfo info = new TableTagInfo(null, type);
+            info.isNull = true;
+            return info;
+        }
+    }
+
+    ;
+
+    public void setTableName(String name) {
+        this.tableName = name;
+    }
+
+    private void ensureTagCapacity(int index) {
+        if (this.tableTags.size() < index + 1) {
+            int delta = index + 1 - this.tableTags.size();
+            this.tableTags.addAll(Collections.nCopies(delta, null));
+        }
+    }
+
+    public void setTagNull(int index, int type) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, TableTagInfo.createNullTag(type));
+    }
+
+    public void setTagBoolean(int index, boolean value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_BOOL));
+        this.tagValueLength += Byte.BYTES;
+    }
+
+    public void setTagInt(int index, int value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_INT));
+        this.tagValueLength += Integer.BYTES;
+    }
+
+    public void setTagByte(int index, byte value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_TINYINT));
+        this.tagValueLength += Byte.BYTES;
+    }
+
+    public void setTagShort(int index, short value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_SMALLINT));
+        this.tagValueLength += Short.BYTES;
+    }
+
+    public void setTagLong(int index, long value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_BIGINT));
+        this.tagValueLength += Long.BYTES;
+    }
+
+    public void setTagTimestamp(int index, long value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP));
+        this.tagValueLength += Long.BYTES;
+    }
+
+    public void setTagFloat(int index, float value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_FLOAT));
+        this.tagValueLength += Float.BYTES;
+    }
+
+    public void setTagDouble(int index, double value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_DOUBLE));
+        this.tagValueLength += Double.BYTES;
+    }
+
+    public void setTagString(int index, String value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_BINARY));
+        this.tagValueLength += value.getBytes().length;
+    }
+
+    public void setTagNString(int index, String value) {
+        ensureTagCapacity(index);
+        this.tableTags.set(index, new TableTagInfo(value, TSDBConstants.TSDB_DATA_TYPE_NCHAR));
+
+        String charset = TaosGlobalConfig.getCharset();
+        try {
+            this.tagValueLength += value.getBytes(charset).length;
+        } catch (UnsupportedEncodingException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public <T> void setValueImpl(int columnIndex, ArrayList<T> list, int type, int bytes) throws SQLException {
+        if (this.colData.size() == 0) {
+            this.colData.addAll(Collections.nCopies(this.parameters.length - 1 - this.tableTags.size(), null));
+        }
+
+        ColumnInfo col = (ColumnInfo) this.colData.get(columnIndex);
+        if (col == null) {
+            ColumnInfo p = new ColumnInfo();
+            p.setType(type);
+            p.bytes = bytes;
+            p.data = (ArrayList<?>) list.clone();
+            this.colData.set(columnIndex, p);
+        } else {
+            if (col.type != type) {
+                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "column data type mismatch");
+            }
+            col.data.addAll(list);
+        }
+    }
+
+    public void setInt(int columnIndex, ArrayList<Integer> list) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_INT, Integer.BYTES);
+    }
+
+    public void setFloat(int columnIndex, ArrayList<Float> list) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_FLOAT, Float.BYTES);
+    }
+
+    public void setTimestamp(int columnIndex, ArrayList<Long> list) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP, Long.BYTES);
+    }
+
+    public void setLong(int columnIndex, ArrayList<Long> list) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_BIGINT, Long.BYTES);
+    }
+
+    public void setDouble(int columnIndex, ArrayList<Double> list) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_DOUBLE, Double.BYTES);
+    }
+
+    public void setBoolean(int columnIndex, ArrayList<Boolean> list) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_BOOL, Byte.BYTES);
+    }
+
+    public void setByte(int columnIndex, ArrayList<Byte> list) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_TINYINT, Byte.BYTES);
+    }
+
+    public void setShort(int columnIndex, ArrayList<Short> list) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_SMALLINT, Short.BYTES);
+    }
+
+    public void setString(int columnIndex, ArrayList<String> list, int size) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_BINARY, size);
+    }
+
+    // note: expand the required space for each NChar character
+    public void setNString(int columnIndex, ArrayList<String> list, int size) throws SQLException {
+        setValueImpl(columnIndex, list, TSDBConstants.TSDB_DATA_TYPE_NCHAR, size * Integer.BYTES);
+    }
+
+    public void columnDataAddBatch() throws SQLException {
+        // pass the data block to native code
+        if (rawSql == null) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "sql statement not set yet");
+        }
+
+        // table name is not set yet, abort
+        if (this.tableName == null) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "table name not set yet");
+        }
+
+        int numOfCols = this.colData.size();
+        if (numOfCols == 0) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "column data not bind");
+        }
+
+        TSDBJNIConnector connector = ((TSDBConnection) this.getConnection()).getConnector();
+        this.nativeStmtHandle = connector.prepareStmt(rawSql);
+
+        if (this.tableTags == null) {
+            connector.setBindTableName(this.nativeStmtHandle, this.tableName);
+        } else {
+            int num = this.tableTags.size();
+            ByteBuffer tagDataList = ByteBuffer.allocate(this.tagValueLength);
+            tagDataList.order(ByteOrder.LITTLE_ENDIAN);
+
+            ByteBuffer typeList = ByteBuffer.allocate(num);
+            typeList.order(ByteOrder.LITTLE_ENDIAN);
+
+            ByteBuffer lengthList = ByteBuffer.allocate(num * Long.BYTES);
+            lengthList.order(ByteOrder.LITTLE_ENDIAN);
+
+            ByteBuffer isNullList = ByteBuffer.allocate(num * Integer.BYTES);
+            isNullList.order(ByteOrder.LITTLE_ENDIAN);
+
+            for (int i = 0; i < num; ++i) {
+                TableTagInfo tag = this.tableTags.get(i);
+                if (tag.isNull) {
+                    typeList.put((byte) tag.type);
+                    isNullList.putInt(1);
+                    lengthList.putLong(0);
+                    continue;
+                }
+
+                switch (tag.type) {
+                    case TSDBConstants.TSDB_DATA_TYPE_INT: {
+                        Integer val = (Integer) tag.value;
+                        tagDataList.putInt(val);
+                        lengthList.putLong(Integer.BYTES);
+                        break;
+                    }
+                    case TSDBConstants.TSDB_DATA_TYPE_TINYINT: {
+                        Byte val = (Byte) tag.value;
+                        tagDataList.put(val);
+                        lengthList.putLong(Byte.BYTES);
+                        break;
+                    }
+
+                    case TSDBConstants.TSDB_DATA_TYPE_BOOL: {
+                        Boolean val = (Boolean) tag.value;
+                        tagDataList.put((byte) (val ? 1 : 0));
+                        lengthList.putLong(Byte.BYTES);
+                        break;
+                    }
+
+                    case TSDBConstants.TSDB_DATA_TYPE_SMALLINT: {
+                        Short val = (Short) tag.value;
+                        tagDataList.putShort(val);
+                        lengthList.putLong(Short.BYTES);
+
+                        break;
+                    }
+
+                    case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
+                    case TSDBConstants.TSDB_DATA_TYPE_BIGINT: {
+                        Long val = (Long) tag.value;
+                        tagDataList.putLong(val == null ? 0 : val);
+                        lengthList.putLong(Long.BYTES);
+
+                        break;
+                    }
+
+                    case TSDBConstants.TSDB_DATA_TYPE_FLOAT: {
+                        Float val = (Float) tag.value;
+                        tagDataList.putFloat(val == null ? 0 : val);
+                        lengthList.putLong(Float.BYTES);
+
+                        break;
+                    }
+
+                    case TSDBConstants.TSDB_DATA_TYPE_DOUBLE: {
+                        Double val = (Double) tag.value;
+                        tagDataList.putDouble(val == null ? 0 : val);
+                        lengthList.putLong(Double.BYTES);
+
+                        break;
+                    }
+
+                    case TSDBConstants.TSDB_DATA_TYPE_NCHAR:
+                    case TSDBConstants.TSDB_DATA_TYPE_BINARY: {
+                        String charset = TaosGlobalConfig.getCharset();
+                        String val = (String) tag.value;
+
+                        byte[] b = null;
+                        try {
+                            if (tag.type == TSDBConstants.TSDB_DATA_TYPE_BINARY) {
+                                b = val.getBytes();
+                            } else {
+                                b = val.getBytes(charset);
+                            }
+                        } catch (UnsupportedEncodingException e) {
+                            e.printStackTrace();
+                        }
+
+                        tagDataList.put(b);
+                        lengthList.putLong(b.length);
+                        break;
+                    }
+
+                    case TSDBConstants.TSDB_DATA_TYPE_UTINYINT:
+                    case TSDBConstants.TSDB_DATA_TYPE_USMALLINT:
+                    case TSDBConstants.TSDB_DATA_TYPE_UINT:
+                    case TSDBConstants.TSDB_DATA_TYPE_UBIGINT: {
+                        throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "not support data types");
+                    }
+                }
+
+                typeList.put((byte) tag.type);
+                isNullList.putInt(tag.isNull ? 1 : 0);
+            }
+
+            connector.setBindTableNameAndTags(this.nativeStmtHandle, this.tableName, this.tableTags.size(), tagDataList,
+                    typeList, lengthList, isNullList);
+        }
+
+        ColumnInfo colInfo = (ColumnInfo) this.colData.get(0);
+        if (colInfo == null) {
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "column data not bind");
+        }
+
+        int rows = colInfo.data.size();
+        for (int i = 0; i < numOfCols; ++i) {
+            ColumnInfo col1 = this.colData.get(i);
+            if (col1 == null || !col1.isTypeSet()) {
+                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "column data not bind");
+            }
+
+            if (rows != col1.data.size()) {
+                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "the rows in column data not identical");
+            }
+
+            ByteBuffer colDataList = ByteBuffer.allocate(rows * col1.bytes);
+            colDataList.order(ByteOrder.LITTLE_ENDIAN);
+
+            ByteBuffer lengthList = ByteBuffer.allocate(rows * Integer.BYTES);
+            lengthList.order(ByteOrder.LITTLE_ENDIAN);
+
+            ByteBuffer isNullList = ByteBuffer.allocate(rows * Byte.BYTES);
+            isNullList.order(ByteOrder.LITTLE_ENDIAN);
+
+            switch (col1.type) {
+                case TSDBConstants.TSDB_DATA_TYPE_INT: {
+                    for (int j = 0; j < rows; ++j) {
+                        Integer val = (Integer) col1.data.get(j);
+                        colDataList.putInt(val == null ? Integer.MIN_VALUE : val);
+                        isNullList.put((byte) (val == null ? 1 : 0));
+                    }
+                    break;
+                }
+
+                case TSDBConstants.TSDB_DATA_TYPE_TINYINT: {
+                    for (int j = 0; j < rows; ++j) {
+                        Byte val = (Byte) col1.data.get(j);
+                        colDataList.put(val == null ? 0 : val);
+                        isNullList.put((byte) (val == null ? 1 : 0));
+                    }
+                    break;
+                }
+
+                case TSDBConstants.TSDB_DATA_TYPE_BOOL: {
+                    for (int j = 0; j < rows; ++j) {
+                        Boolean val = (Boolean) col1.data.get(j);
+                        if (val == null) {
+                            colDataList.put((byte) 0);
+                        } else {
+                            colDataList.put((byte) (val ? 1 : 0));
+                        }
+
+                        isNullList.put((byte) (val == null ? 1 : 0));
+                    }
+                    break;
+                }
+
+                case TSDBConstants.TSDB_DATA_TYPE_SMALLINT: {
+                    for (int j = 0; j < rows; ++j) {
+                        Short val = (Short) col1.data.get(j);
+                        colDataList.putShort(val == null ? 0 : val);
+                        isNullList.put((byte) (val == null ? 1 : 0));
+                    }
+                    break;
+                }
+
+                case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
+                case TSDBConstants.TSDB_DATA_TYPE_BIGINT: {
+                    for (int j = 0; j < rows; ++j) {
+                        Long val = (Long) col1.data.get(j);
+                        colDataList.putLong(val == null ? 0 : val);
+                        isNullList.put((byte) (val == null ? 1 : 0));
+                    }
+                    break;
+                }
+
+                case TSDBConstants.TSDB_DATA_TYPE_FLOAT: {
+                    for (int j = 0; j < rows; ++j) {
+                        Float val = (Float) col1.data.get(j);
+                        colDataList.putFloat(val == null ? 0 : val);
+                        isNullList.put((byte) (val == null ? 1 : 0));
+                    }
+                    break;
+                }
+
+                case TSDBConstants.TSDB_DATA_TYPE_DOUBLE: {
+                    for (int j = 0; j < rows; ++j) {
+                        Double val = (Double) col1.data.get(j);
+                        colDataList.putDouble(val == null ? 0 : val);
+                        isNullList.put((byte) (val == null ? 1 : 0));
+                    }
+                    break;
+                }
+
+                case TSDBConstants.TSDB_DATA_TYPE_NCHAR:
+                case TSDBConstants.TSDB_DATA_TYPE_BINARY: {
+                    String charset = TaosGlobalConfig.getCharset();
+                    for (int j = 0; j < rows; ++j) {
+                        String val = (String) col1.data.get(j);
+
+                        colDataList.position(j * col1.bytes);  // seek to the correct position
+                        if (val != null) {
+                            byte[] b = null;
+                            try {
+                                if (col1.type == TSDBConstants.TSDB_DATA_TYPE_BINARY) {
+                                    b = val.getBytes();
+                                } else {
+                                    b = val.getBytes(charset);
+                                }
+                            } catch (UnsupportedEncodingException e) {
+                                e.printStackTrace();
+                            }
+
+                            if (val.length() > col1.bytes) {
+                                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "string data too long");
+                            }
+
+                            colDataList.put(b);
+                            lengthList.putInt(b.length);
+                            isNullList.put((byte) 0);
+                        } else {
+                            lengthList.putInt(0);
+                            isNullList.put((byte) 1);
+                        }
+                    }
+                    break;
+                }
+
+                case TSDBConstants.TSDB_DATA_TYPE_UTINYINT:
+                case TSDBConstants.TSDB_DATA_TYPE_USMALLINT:
+                case TSDBConstants.TSDB_DATA_TYPE_UINT:
+                case TSDBConstants.TSDB_DATA_TYPE_UBIGINT: {
+                    throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNKNOWN, "not support data types");
+                }
+            }
+            ;
+
+            connector.bindColumnDataArray(this.nativeStmtHandle, colDataList, lengthList, isNullList, col1.type, col1.bytes, rows, i);
+        }
+    }
+
+    public void columnDataExecuteBatch() throws SQLException {
+        TSDBJNIConnector connector = ((TSDBConnection) this.getConnection()).getConnector();
+        connector.executeBatch(this.nativeStmtHandle);
+        this.columnDataClearBatch();
+    }
+
+    public void columnDataClearBatch() {
+        int size = this.colData.size();
+        this.colData.clear();
+
+        this.colData.addAll(Collections.nCopies(size, null));
+        this.tableName = null;   // clear the table name
+    }
+
+    public void columnDataCloseBatch() throws SQLException {
+        TSDBJNIConnector connector = ((TSDBConnection) this.getConnection()).getConnector();
+        connector.closeBatch(this.nativeStmtHandle);
+
+        this.nativeStmtHandle = 0L;
+        this.tableName = null;
+    }
 }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBResultSet.java

@@ -133,9 +133,10 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return this.blockData.getString(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            res = this.rowData.getString(columnIndex - 1, this.columnMetaDataList.get(columnIndex - 1).getColType());
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            res = this.rowData.getString(columnIndex, nativeType);
         }
         return res;
     }
@@ -147,9 +148,10 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return this.blockData.getBoolean(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            res = this.rowData.getBoolean(columnIndex - 1, this.columnMetaDataList.get(columnIndex - 1).getColType());
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            res = this.rowData.getBoolean(columnIndex, nativeType);
         }
         return res;
     }
@@ -161,9 +163,10 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return (byte) this.blockData.getInt(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            res = (byte) this.rowData.getInt(columnIndex - 1, this.columnMetaDataList.get(columnIndex - 1).getColType());
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            res = (byte) this.rowData.getInt(columnIndex, nativeType);
         }
         return res;
     }
@@ -175,9 +178,10 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return (short) this.blockData.getInt(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            res = (short) this.rowData.getInt(columnIndex - 1, this.columnMetaDataList.get(columnIndex - 1).getColType());
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            res = (short) this.rowData.getInt(columnIndex, nativeType);
         }
         return res;
     }
@@ -189,9 +193,11 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return this.blockData.getInt(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            res = this.rowData.getInt(columnIndex - 1, this.columnMetaDataList.get(columnIndex - 1).getColType());
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            res = this.rowData.getInt(columnIndex, nativeType);
         }
         return res;
     }
@@ -203,13 +209,15 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return this.blockData.getLong(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            Object value = this.rowData.get(columnIndex - 1);
-            if (value instanceof Timestamp)
+            Object value = this.rowData.getObject(columnIndex);
+            if (value instanceof Timestamp) {
                 res = ((Timestamp) value).getTime();
-            else
-                res = this.rowData.getLong(columnIndex - 1, this.columnMetaDataList.get(columnIndex - 1).getColType());
+            } else {
+                int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+                res = this.rowData.getLong(columnIndex, nativeType);
+            }
         }
         return res;
     }
@@ -221,9 +229,11 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return (float) this.blockData.getDouble(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
-        if (!lastWasNull)
-            res = this.rowData.getFloat(columnIndex - 1, this.columnMetaDataList.get(columnIndex - 1).getColType());
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
+        if (!lastWasNull) {
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            res = this.rowData.getFloat(columnIndex, nativeType);
+        }
 
         return res;
     }
@@ -235,9 +245,10 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return this.blockData.getDouble(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            res = this.rowData.getDouble(columnIndex - 1, this.columnMetaDataList.get(columnIndex - 1).getColType());
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            res = this.rowData.getDouble(columnIndex, nativeType);
         }
         return res;
     }
@@ -245,34 +256,27 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
     public byte[] getBytes(int columnIndex) throws SQLException {
         checkAvailability(columnIndex, this.columnMetaDataList.size());
 
-        Object value = this.rowData.get(columnIndex - 1);
+        Object value = this.rowData.getObject(columnIndex);
         if (value == null)
             return null;
 
-        int colType = this.columnMetaDataList.get(columnIndex - 1).getColType();
-        switch (colType) {
+        int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+        switch (nativeType) {
             case TSDBConstants.TSDB_DATA_TYPE_BIGINT:
-                return Longs.toByteArray((Long) value);
+                return Longs.toByteArray((long) value);
             case TSDBConstants.TSDB_DATA_TYPE_INT:
                 return Ints.toByteArray((int) value);
             case TSDBConstants.TSDB_DATA_TYPE_SMALLINT:
-                return Shorts.toByteArray((Short) value);
+                return Shorts.toByteArray((short) value);
             case TSDBConstants.TSDB_DATA_TYPE_TINYINT:
                 return new byte[]{(byte) value};
+            case TSDBConstants.TSDB_DATA_TYPE_BINARY:
+                return (byte[]) value;
+            case TSDBConstants.TSDB_DATA_TYPE_BOOL:
+            case TSDBConstants.TSDB_DATA_TYPE_NCHAR:
+            default:
+                return value.toString().getBytes();
         }
-        return value.toString().getBytes();
-    }
-
-    @Override
-    public Date getDate(int columnIndex) throws SQLException {
-        Timestamp timestamp = getTimestamp(columnIndex);
-        return timestamp == null ? null : new Date(timestamp.getTime());
-    }
-
-    @Override
-    public Time getTime(int columnIndex) throws SQLException {
-        Timestamp timestamp = getTimestamp(columnIndex);
-        return timestamp == null ? null : new Time(timestamp.getTime());
     }
 
     public Timestamp getTimestamp(int columnIndex) throws SQLException {
@@ -282,9 +286,10 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return this.blockData.getTimestamp(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            res = this.rowData.getTimestamp(columnIndex - 1);
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            res = this.rowData.getTimestamp(columnIndex, nativeType);
         }
         return res;
     }
@@ -304,13 +309,9 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return this.blockData.get(columnIndex - 1);
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         if (!lastWasNull) {
-            int colType = this.columnMetaDataList.get(columnIndex - 1).getColType();
-            if (colType == TSDBConstants.TSDB_DATA_TYPE_BINARY)
-                res = ((String) this.rowData.get(columnIndex - 1)).getBytes();
-            else
-                res = this.rowData.get(columnIndex - 1);
+            res = this.rowData.getObject(columnIndex);
         }
         return res;
     }
@@ -318,7 +319,7 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
     public int findColumn(String columnLabel) throws SQLException {
         for (ColumnMetaData colMetaData : this.columnMetaDataList) {
             if (colMetaData.getColName() != null && colMetaData.getColName().equalsIgnoreCase(columnLabel)) {
-                return colMetaData.getColIndex() + 1;
+                return colMetaData.getColIndex();
             }
         }
         throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_INVALID_VARIABLE);
@@ -329,25 +330,25 @@ public class TSDBResultSet extends AbstractResultSet implements ResultSet {
         if (this.getBatchFetch())
             return new BigDecimal(this.blockData.getLong(columnIndex - 1));
 
-        this.lastWasNull = this.rowData.wasNull(columnIndex - 1);
+        this.lastWasNull = this.rowData.wasNull(columnIndex);
         BigDecimal res = null;
         if (!lastWasNull) {
-            int colType = this.columnMetaDataList.get(columnIndex - 1).getColType();
-            switch (colType) {
+            int nativeType = this.columnMetaDataList.get(columnIndex - 1).getColType();
+            switch (nativeType) {
                 case TSDBConstants.TSDB_DATA_TYPE_TINYINT:
                 case TSDBConstants.TSDB_DATA_TYPE_SMALLINT:
                 case TSDBConstants.TSDB_DATA_TYPE_INT:
                 case TSDBConstants.TSDB_DATA_TYPE_BIGINT:
-                    res = new BigDecimal(Long.valueOf(this.rowData.get(columnIndex - 1).toString()));
+                    res = new BigDecimal(Long.valueOf(this.rowData.getObject(columnIndex).toString()));
                     break;
                 case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
                 case TSDBConstants.TSDB_DATA_TYPE_DOUBLE:
-                    res = new BigDecimal(Double.valueOf(this.rowData.get(columnIndex - 1).toString()));
+                    res = new BigDecimal(Double.valueOf(this.rowData.getObject(columnIndex).toString()));
                     break;
                 case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
-                    return new BigDecimal(((Timestamp) this.rowData.get(columnIndex - 1)).getTime());
+                    return new BigDecimal(((Timestamp) this.rowData.getObject(columnIndex)).getTime());
                 default:
-                    res = new BigDecimal(this.rowData.get(columnIndex - 1).toString());
+                    res = new BigDecimal(this.rowData.getObject(columnIndex).toString());
             }
         }
         return res;

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBResultSetBlockData.java

@@ -29,6 +29,8 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
+import com.taosdata.jdbc.utils.NullType;
+
 public class TSDBResultSetBlockData {
     private int numOfRows = 0;
     private int rowIndex = 0;
@@ -164,59 +166,7 @@ public class TSDBResultSetBlockData {
         }
     }
 
-    private static class NullType {
-        private static final byte NULL_BOOL_VAL = 0x2;
-        private static final String NULL_STR = "null";
-
-        public String toString() {
-            return NullType.NULL_STR;
-        }
-
-        public static boolean isBooleanNull(byte val) {
-            return val == NullType.NULL_BOOL_VAL;
-        }
-
-        private static boolean isTinyIntNull(byte val) {
-            return val == Byte.MIN_VALUE;
-        }
-
-        private static boolean isSmallIntNull(short val) {
-            return val == Short.MIN_VALUE;
-        }
-
-        private static boolean isIntNull(int val) {
-            return val == Integer.MIN_VALUE;
-        }
-
-        private static boolean isBigIntNull(long val) {
-            return val == Long.MIN_VALUE;
-        }
-
-        private static boolean isFloatNull(float val) {
-            return Float.isNaN(val);
-        }
-
-        private static boolean isDoubleNull(double val) {
-            return Double.isNaN(val);
-        }
-
-        private static boolean isBinaryNull(byte[] val, int length) {
-            if (length != Byte.BYTES) {
-                return false;
-            }
-
-            return val[0] == 0xFF;
-        }
-
-        private static boolean isNcharNull(byte[] val, int length) {
-            if (length != Integer.BYTES) {
-                return false;
-            }
-
-            return (val[0] & val[1] & val[2] & val[3]) == 0xFF;
-        }
-
-    }
+    
 
     /**
      * The original type may not be a string type, but will be converted to by
@@ -488,8 +438,8 @@ public class TSDBResultSetBlockData {
                 }
 
                 try {
-                    String ss = TaosGlobalConfig.getCharset();
-                    return new String(dest, ss);
+                    String charset = TaosGlobalConfig.getCharset();
+                    return new String(dest, charset);
                 } catch (UnsupportedEncodingException e) {
                     e.printStackTrace();
                 }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBResultSetMetaData.java

@@ -113,6 +113,7 @@ public class TSDBResultSetMetaData extends WrapperImpl implements ResultSetMetaD
 
         ColumnMetaData columnMetaData = this.colMetaDataList.get(column - 1);
         switch (columnMetaData.getColType()) {
+            
             case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
                 return 5;
             case TSDBConstants.TSDB_DATA_TYPE_DOUBLE:

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBResultSetRowData.java

@@ -14,6 +14,8 @@
  *****************************************************************************/
 package com.taosdata.jdbc;
 
+import com.taosdata.jdbc.utils.NullType;
+
 import java.math.BigDecimal;
 import java.sql.SQLException;
 import java.sql.Timestamp;
@@ -22,11 +24,13 @@ import java.util.ArrayList;
 import java.util.Collections;
 
 public class TSDBResultSetRowData {
+
     private ArrayList<Object> data;
-    private int colSize = 0;
+    private int colSize;
 
     public TSDBResultSetRowData(int colSize) {
-        this.setColSize(colSize);
+        this.colSize = colSize;
+        this.clear();
     }
 
     public void clear() {
@@ -41,67 +45,104 @@ public class TSDBResultSetRowData {
     }
 
     public boolean wasNull(int col) {
-        return data.get(col) == null;
+        return data.get(col - 1) == null;
+    }
+
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setBooleanValue(int col, boolean value) {
+        setBoolean(col - 1, value);
     }
 
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setBoolean(int col, boolean value) {
         data.set(col, value);
     }
 
-    public boolean getBoolean(int col, int srcType) throws SQLException {
-        Object obj = data.get(col);
+    public boolean getBoolean(int col, int nativeType) throws SQLException {
+        Object obj = data.get(col - 1);
 
-        switch (srcType) {
+        switch (nativeType) {
             case TSDBConstants.TSDB_DATA_TYPE_BOOL:
                 return (Boolean) obj;
-            case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
-                return ((Float) obj) == 1.0 ? Boolean.TRUE : Boolean.FALSE;
-            case TSDBConstants.TSDB_DATA_TYPE_DOUBLE:
-                return ((Double) obj) == 1.0 ? Boolean.TRUE : Boolean.FALSE;
             case TSDBConstants.TSDB_DATA_TYPE_TINYINT:
                 return ((Byte) obj) == 1 ? Boolean.TRUE : Boolean.FALSE;
             case TSDBConstants.TSDB_DATA_TYPE_SMALLINT:
                 return ((Short) obj) == 1 ? Boolean.TRUE : Boolean.FALSE;
             case TSDBConstants.TSDB_DATA_TYPE_INT:
                 return ((Integer) obj) == 1 ? Boolean.TRUE : Boolean.FALSE;
-            case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
             case TSDBConstants.TSDB_DATA_TYPE_BIGINT:
                 return ((Long) obj) == 1L ? Boolean.TRUE : Boolean.FALSE;
+            case TSDBConstants.TSDB_DATA_TYPE_BINARY:
+            case TSDBConstants.TSDB_DATA_TYPE_NCHAR: {
+                return obj.toString().contains("1");
+            }
             default:
                 return false;
         }
     }
 
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setByteValue(int colIndex, byte value) {
+        setByte(colIndex - 1, value);
+    }
+
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setByte(int col, byte value) {
         data.set(col, value);
     }
 
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setShortValue(int colIndex, short value) {
+        setShort(colIndex - 1, value);
+    }
+
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setShort(int col, short value) {
         data.set(col, value);
     }
 
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setIntValue(int colIndex, int value) {
+        setInt(colIndex - 1, value);
+    }
+
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setInt(int col, int value) {
         data.set(col, value);
     }
 
-    public int getInt(int col, int srcType) throws SQLException {
-        Object obj = data.get(col);
+    public int getInt(int col, int nativeType) throws SQLException {
+        Object obj = data.get(col - 1);
+        if (obj == null)
+            return NullType.getIntNull();
 
-        switch (srcType) {
+        switch (nativeType) {
             case TSDBConstants.TSDB_DATA_TYPE_BOOL:
                 return Boolean.TRUE.equals(obj) ? 1 : 0;
-            case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
-                return ((Float) obj).intValue();
-            case TSDBConstants.TSDB_DATA_TYPE_DOUBLE:
-                return ((Double) obj).intValue();
             case TSDBConstants.TSDB_DATA_TYPE_TINYINT:
                 return (Byte) obj;
             case TSDBConstants.TSDB_DATA_TYPE_SMALLINT:
                 return (Short) obj;
             case TSDBConstants.TSDB_DATA_TYPE_INT:
                 return (Integer) obj;
-            case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
             case TSDBConstants.TSDB_DATA_TYPE_BIGINT:
+            case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
                 return ((Long) obj).intValue();
             case TSDBConstants.TSDB_DATA_TYPE_NCHAR:
             case TSDBConstants.TSDB_DATA_TYPE_BINARY:
@@ -128,35 +169,48 @@ public class TSDBResultSetRowData {
                 long value = (long) obj;
                 if (value < 0)
                     throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_NUMERIC_VALUE_OUT_OF_RANGE);
-                return new Long(value).intValue();
+                return Long.valueOf(value).intValue();
             }
+            case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
+                return ((Float) obj).intValue();
+            case TSDBConstants.TSDB_DATA_TYPE_DOUBLE:
+                return ((Double) obj).intValue();
+            default:
+                return 0;
         }
+    }
 
-        return 0;
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setLongValue(int colIndex, long value) {
+        setLong(colIndex - 1, value);
     }
 
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setLong(int col, long value) {
         data.set(col, value);
     }
 
-    public long getLong(int col, int srcType) throws SQLException {
-        Object obj = data.get(col);
+    public long getLong(int col, int nativeType) throws SQLException {
+        Object obj = data.get(col - 1);
+        if (obj == null) {
+            return NullType.getBigIntNull();
+        }
 
-        switch (srcType) {
+        switch (nativeType) {
             case TSDBConstants.TSDB_DATA_TYPE_BOOL:
                 return Boolean.TRUE.equals(obj) ? 1 : 0;
-            case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
-                return ((Float) obj).longValue();
-            case TSDBConstants.TSDB_DATA_TYPE_DOUBLE:
-                return ((Double) obj).longValue();
             case TSDBConstants.TSDB_DATA_TYPE_TINYINT:
                 return (Byte) obj;
             case TSDBConstants.TSDB_DATA_TYPE_SMALLINT:
                 return (Short) obj;
             case TSDBConstants.TSDB_DATA_TYPE_INT:
                 return (Integer) obj;
-            case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
             case TSDBConstants.TSDB_DATA_TYPE_BIGINT:
+            case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
                 return (Long) obj;
             case TSDBConstants.TSDB_DATA_TYPE_NCHAR:
             case TSDBConstants.TSDB_DATA_TYPE_BINARY:
@@ -185,19 +239,35 @@ public class TSDBResultSetRowData {
                     throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_NUMERIC_VALUE_OUT_OF_RANGE);
                 return value;
             }
+            case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
+                return ((Float) obj).longValue();
+            case TSDBConstants.TSDB_DATA_TYPE_DOUBLE:
+                return ((Double) obj).longValue();
+            default:
+                return 0;
         }
+    }
 
-        return 0;
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setFloatValue(int colIndex, float value) {
+        setFloat(colIndex - 1, value);
     }
 
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setFloat(int col, float value) {
         data.set(col, value);
     }
 
-    public float getFloat(int col, int srcType) {
-        Object obj = data.get(col);
+    public float getFloat(int col, int nativeType) {
+        Object obj = data.get(col - 1);
+        if (obj == null)
+            return NullType.getFloatNull();
 
-        switch (srcType) {
+        switch (nativeType) {
             case TSDBConstants.TSDB_DATA_TYPE_BOOL:
                 return Boolean.TRUE.equals(obj) ? 1 : 0;
             case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
@@ -213,19 +283,31 @@ public class TSDBResultSetRowData {
             case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
             case TSDBConstants.TSDB_DATA_TYPE_BIGINT:
                 return (Long) obj;
+            default:
+                return NullType.getFloatNull();
         }
+    }
 
-        return 0;
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setDoubleValue(int colIndex, double value) {
+        setDouble(colIndex - 1, value);
     }
 
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setDouble(int col, double value) {
         data.set(col, value);
     }
 
-    public double getDouble(int col, int srcType) {
-        Object obj = data.get(col);
+    public double getDouble(int col, int nativeType) {
+        Object obj = data.get(col - 1);
+        if (obj == null)
+            return NullType.getDoubleNull();
 
-        switch (srcType) {
+        switch (nativeType) {
             case TSDBConstants.TSDB_DATA_TYPE_BOOL:
                 return Boolean.TRUE.equals(obj) ? 1 : 0;
             case TSDBConstants.TSDB_DATA_TYPE_FLOAT:
@@ -241,16 +323,46 @@ public class TSDBResultSetRowData {
             case TSDBConstants.TSDB_DATA_TYPE_TIMESTAMP:
             case TSDBConstants.TSDB_DATA_TYPE_BIGINT:
                 return (Long) obj;
+            default:
+                return NullType.getDoubleNull();
         }
+    }
 
-        return 0;
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setStringValue(int colIndex, String value) {
+        data.set(colIndex - 1, value);
     }
 
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setString(int col, String value) {
-        data.set(col, value);
+        // TODO:
+        //  !!!NOTE!!!
+        //  this is very confusing problem which related to JNI-method implementation,
+        //  the JNI method return a String(encoded in UTF) for BINARY value, which means the JNI method will invoke
+        //  this setString(int, String) to handle BINARY value, we need to build a byte[] with default charsetEncoding
+        data.set(col, value == null ? null : value.getBytes());
+    }
+
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setByteArrayValue(int colIndex, byte[] value) {
+        setByteArray(colIndex - 1, value);
     }
 
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setByteArray(int col, byte[] value) {
+        // TODO:
+        //  !!!NOTE!!!
+        //  this is very confusing problem which related to JNI-method implementation,
+        //  the JNI method return a byte[] for NCHAR value, which means the JNI method will invoke
+        //  this setByteArr(int, byte[]) to handle NCHAR value, we need to build a String with charsetEncoding by TaosGlobalConfig
         try {
             data.set(col, new String(value, TaosGlobalConfig.getCharset()));
         } catch (Exception e) {
@@ -258,47 +370,56 @@ public class TSDBResultSetRowData {
         }
     }
 
-    /**
-     * The original type may not be a string type, but will be converted to by calling this method
-     *
-     * @param col column index
-     * @return
-     */
-    public String getString(int col, int srcType) {
-        switch (srcType) {
-            case TSDBConstants.TSDB_DATA_TYPE_BINARY:
-            case TSDBConstants.TSDB_DATA_TYPE_NCHAR:
-                return (String) data.get(col);
+    public String getString(int col, int nativeType) {
+        Object obj = data.get(col - 1);
+        if (obj == null)
+            return null;
+
+        switch (nativeType) {
             case TSDBConstants.TSDB_DATA_TYPE_UTINYINT: {
-                Byte value = new Byte(String.valueOf(data.get(col)));
+                Byte value = new Byte(String.valueOf(obj));
                 if (value >= 0)
                     return value.toString();
                 return Integer.toString(value & 0xff);
             }
             case TSDBConstants.TSDB_DATA_TYPE_USMALLINT: {
-                Short value = new Short(String.valueOf(data.get(col)));
+                Short value = new Short(String.valueOf(obj));
                 if (value >= 0)
                     return value.toString();
                 return Integer.toString(value & 0xffff);
             }
             case TSDBConstants.TSDB_DATA_TYPE_UINT: {
-                Integer value = new Integer(String.valueOf(data.get(col)));
+                Integer value = new Integer(String.valueOf(obj));
                 if (value >= 0)
                     return value.toString();
                 return Long.toString(value & 0xffffffffl);
             }
             case TSDBConstants.TSDB_DATA_TYPE_UBIGINT: {
-                Long value = new Long(String.valueOf(data.get(col)));
+                Long value = new Long(String.valueOf(obj));
                 if (value >= 0)
                     return value.toString();
                 long lowValue = value & 0x7fffffffffffffffL;
                 return BigDecimal.valueOf(lowValue).add(BigDecimal.valueOf(Long.MAX_VALUE)).add(BigDecimal.valueOf(1)).toString();
             }
+            case TSDBConstants.TSDB_DATA_TYPE_BINARY:
+                return new String((byte[]) obj);
+            case TSDBConstants.TSDB_DATA_TYPE_NCHAR:
+                return (String) obj;
             default:
-                return String.valueOf(data.get(col));
+                return String.valueOf(obj);
         }
     }
 
+    /**
+     * $$$ this method is invoked by databaseMetaDataResultSet and so on which use a index start from 1 in JDBC api
+     */
+    public void setTimestampValue(int colIndex, long value) {
+        setTimestamp(colIndex - 1, value);
+    }
+
+    /**
+     * !!! this method is invoked by JNI method and the index start from 0 in C implementations
+     */
     public void setTimestamp(int col, long ts) {
         //TODO: this implementation contains logical error
         // when precision is us the (long ts) is 16 digital number
@@ -315,28 +436,20 @@ public class TSDBResultSetRowData {
         }
     }
 
-    public Timestamp getTimestamp(int col) {
-        return (Timestamp) data.get(col);
-    }
-
-    public Object get(int col) {
-        return data.get(col);
-    }
-
-    public int getColSize() {
-        return colSize;
-    }
-
-    private void setColSize(int colSize) {
-        this.colSize = colSize;
-        this.clear();
+    public Timestamp getTimestamp(int col, int nativeType) {
+        Object obj = data.get(col - 1);
+        if (obj == null)
+            return null;
+        switch (nativeType) {
+            case TSDBConstants.TSDB_DATA_TYPE_BIGINT:
+                return new Timestamp((Long) obj);
+            default:
+                return (Timestamp) obj;
+        }
     }
 
-    public ArrayList<Object> getData() {
-        return data;
+    public Object getObject(int col) {
+        return data.get(col - 1);
     }
 
-    public void setData(ArrayList<Object> data) {
-        this.data = (ArrayList<Object>) data.clone();
-    }
 }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBStatement.java

@@ -19,8 +19,6 @@ import java.sql.ResultSet;
 import java.sql.SQLException;
 
 public class TSDBStatement extends AbstractStatement {
-
-    private TSDBJNIConnector connector;
     /**
      * Status of current statement
      */
@@ -29,29 +27,27 @@ public class TSDBStatement extends AbstractStatement {
     private TSDBConnection connection;
     private TSDBResultSet resultSet;
 
-    public void setConnection(TSDBConnection connection) {
-        this.connection = connection;
-    }
-
-    TSDBStatement(TSDBConnection connection, TSDBJNIConnector connector) {
+    TSDBStatement(TSDBConnection connection) {
         this.connection = connection;
-        this.connector = connector;
     }
 
     public ResultSet executeQuery(String sql) throws SQLException {
-        // check if closed
-        if (isClosed())
+        if (isClosed()) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-        //TODO: 如果在executeQuery方法中执行insert语句，那么先执行了SQL，再通过pSql来检查是否为一个insert语句，但这个insert SQL已经执行成功了
-
-        // execute query
-        long pSql = this.connector.executeQuery(sql);
+        }
+        //TODO:
+        // this is an unreasonable implementation, if the paratemer is a insert statement,
+        // the JNI connector will execute the sql at first and return a pointer: pSql,
+        // we use this pSql and invoke the isUpdateQuery(long pSql) method to decide .
+        // but the insert sql is already executed in database.
+        //execute query
+        long pSql = this.connection.getConnector().executeQuery(sql);
         // if pSql is create/insert/update/delete/alter SQL
-        if (this.connector.isUpdateQuery(pSql)) {
-            this.connector.freeResultSet(pSql);
+        if (this.connection.getConnector().isUpdateQuery(pSql)) {
+            this.connection.getConnector().freeResultSet(pSql);
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_INVALID_WITH_EXECUTEQUERY);
         }
-        TSDBResultSet res = new TSDBResultSet(this, this.connector, pSql);
+        TSDBResultSet res = new TSDBResultSet(this, this.connection.getConnector(), pSql);
         res.setBatchFetch(this.connection.getBatchFetch());
         return res;
     }
@@ -60,14 +56,14 @@ public class TSDBStatement extends AbstractStatement {
         if (isClosed())
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
 
-        long pSql = this.connector.executeQuery(sql);
+        long pSql = this.connection.getConnector().executeQuery(sql);
         // if pSql is create/insert/update/delete/alter SQL
-        if (!this.connector.isUpdateQuery(pSql)) {
-            this.connector.freeResultSet(pSql);
+        if (!this.connection.getConnector().isUpdateQuery(pSql)) {
+            this.connection.getConnector().freeResultSet(pSql);
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_INVALID_WITH_EXECUTEUPDATE);
         }
-        int affectedRows = this.connector.getAffectedRows(pSql);
-        this.connector.freeResultSet(pSql);
+        int affectedRows = this.connection.getConnector().getAffectedRows(pSql);
+        this.connection.getConnector().freeResultSet(pSql);
         return affectedRows;
     }
 
@@ -81,30 +77,29 @@ public class TSDBStatement extends AbstractStatement {
 
     public boolean execute(String sql) throws SQLException {
         // check if closed
-        if (isClosed())
+        if (isClosed()) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
+        }
+        
         // execute query
-        long pSql = this.connector.executeQuery(sql);
+        long pSql = this.connection.getConnector().executeQuery(sql);
         // if pSql is create/insert/update/delete/alter SQL
-        if (this.connector.isUpdateQuery(pSql)) {
-            this.affectedRows = this.connector.getAffectedRows(pSql);
-            this.connector.freeResultSet(pSql);
+        if (this.connection.getConnector().isUpdateQuery(pSql)) {
+            this.affectedRows = this.connection.getConnector().getAffectedRows(pSql);
+            this.connection.getConnector().freeResultSet(pSql);
             return false;
         }
 
-        this.resultSet = new TSDBResultSet(this, this.connector, pSql);
+        this.resultSet = new TSDBResultSet(this, this.connection.getConnector(), pSql);
         this.resultSet.setBatchFetch(this.connection.getBatchFetch());
         return true;
     }
 
     public ResultSet getResultSet() throws SQLException {
-        if (isClosed())
+        if (isClosed()) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-//        long resultSetPointer = connector.getResultSet();
-//        TSDBResultSet resSet = null;
-//        if (resultSetPointer != TSDBConstants.JNI_NULL_POINTER) {
-//            resSet = new TSDBResultSet(connector, resultSetPointer);
-//        }
+        }
+        
         return this.resultSet;
     }
 
@@ -115,12 +110,20 @@ public class TSDBStatement extends AbstractStatement {
     }
 
     public Connection getConnection() throws SQLException {
-        if (isClosed())
+        if (isClosed()) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_STATEMENT_CLOSED);
-        if (this.connector == null)
+        }
+        
+        if (this.connection.getConnector() == null) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_JNI_CONNECTION_NULL);
+        }
+        
         return this.connection;
     }
+    
+    public void setConnection(TSDBConnection connection) {
+        this.connection = connection;
+    }
 
     public boolean isClosed() throws SQLException {
         return isClosed;

src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/NullType.java

+package com.taosdata.jdbc.utils;
+
+public class NullType {
+    private static final byte NULL_BOOL_VAL = 0x2;
+    private static final String NULL_STR = "null";
+
+    public String toString() {
+        return NullType.NULL_STR;
+    }
+
+    public static boolean isBooleanNull(byte val) {
+        return val == NullType.NULL_BOOL_VAL;
+    }
+    
+    public static boolean isTinyIntNull(byte val) {
+        return val == Byte.MIN_VALUE;
+    }
+    
+    public static boolean isSmallIntNull(short val) {
+        return val == Short.MIN_VALUE;
+    }
+
+    public static boolean isIntNull(int val) {
+        return val == Integer.MIN_VALUE;
+    }
+    
+    public static boolean isBigIntNull(long val) {
+        return val == Long.MIN_VALUE;
+    }
+    
+    public static boolean isFloatNull(float val) {
+        return Float.isNaN(val);
+    }
+    
+    public static boolean isDoubleNull(double val) {
+        return Double.isNaN(val);
+    }
+    
+    public static boolean isBinaryNull(byte[] val, int length) {
+        if (length != Byte.BYTES) {
+            return false;
+        }
+
+        return val[0] == 0xFF;
+    }
+    
+    public static boolean isNcharNull(byte[] val, int length) {
+        if (length != Integer.BYTES) {
+            return false;
+        }
+
+        return (val[0] & val[1] & val[2] & val[3]) == 0xFF;
+    }
+    
+    public static byte getBooleanNull() {
+    	return NullType.NULL_BOOL_VAL;
+    }
+    
+    public static byte getTinyintNull() {
+    	return Byte.MIN_VALUE;
+    }
+    
+    public static int getIntNull() {
+    	return Integer.MIN_VALUE;
+    }
+    
+    public static short getSmallIntNull() {
+    	return Short.MIN_VALUE;
+    }
+
+    public static long getBigIntNull() {
+    	return Long.MIN_VALUE;
+    }
+    
+    public static int getFloatNull() {
+    	return 0x7FF00000;
+    }
+
+    public static long getDoubleNull() {
+    	return 0x7FFFFF0000000000L;
+    }
+
+    public static byte getBinaryNull() {
+    	return (byte) 0xFF;
+    }
+    
+    public static byte[] getNcharNull() {
+    	return new byte[] {(byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF};
+    }
+
+}

src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/Utils.java

@@ -95,16 +95,7 @@ public class Utils {
     public static String getNativeSql(String rawSql, Object[] parameters) {
         // toLowerCase
         String preparedSql = rawSql.trim().toLowerCase();
-
-        String[] clause = new String[0];
-        if (SqlSyntaxValidator.isInsertSql(preparedSql)) {
-            // insert or import
-            clause = new String[]{"values\\s*\\(.*?\\)", "tags\\s*\\(.*?\\)"};
-        }
-        if (SqlSyntaxValidator.isSelectSql(preparedSql)) {
-            // select
-            clause = new String[]{"where\\s*.*"};
-        }
+        String[] clause = new String[]{"values\\s*\\(.*?\\)", "tags\\s*\\(.*?\\)", "where\\s*.*"};
         Map<Integer, Integer> placeholderPositions = new HashMap<>();
         RangeSet<Integer> clauseRangeSet = TreeRangeSet.create();
         findPlaceholderPosition(preparedSql, placeholderPositions);
@@ -146,6 +137,7 @@ public class Utils {
      */
     private static String transformSql(String rawSql, Object[] paramArr, Map<Integer, Integer> placeholderPosition, RangeSet<Integer> clauseRangeSet) {
         String[] sqlArr = rawSql.split("\\?");
+
         return IntStream.range(0, sqlArr.length).mapToObj(index -> {
             if (index == paramArr.length)
                 return sqlArr[index];

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBConnectionTest.java

@@ -32,20 +32,34 @@ public class TSDBConnectionTest {
     }
 
     @Test
-    public void subscribe() {
+    public void runSubscribe() {
         try {
+            // given
             TSDBConnection unwrap = conn.unwrap(TSDBConnection.class);
             TSDBSubscribe subscribe = unwrap.subscribe("topic1", "select * from log.log", false);
+            // when
             TSDBResultSet rs = subscribe.consume();
             ResultSetMetaData metaData = rs.getMetaData();
-            for (int count = 0; count < 10 && rs.next(); count++) {
-                for (int i = 1; i <= metaData.getColumnCount(); i++) {
-                    String value = rs.getString(i);
-                    System.out.print(metaData.getColumnLabel(i) + ":" + value + "\t");
-                }
-                System.out.println();
-            }
+
+            // then
             Assert.assertNotNull(rs);
+            Assert.assertEquals(4, metaData.getColumnCount());
+            Assert.assertEquals("ts", metaData.getColumnLabel(1));
+            Assert.assertEquals("level", metaData.getColumnLabel(2));
+            Assert.assertEquals("content", metaData.getColumnLabel(3));
+            Assert.assertEquals("ipaddr", metaData.getColumnLabel(4));
+            rs.next();
+            // row 1
+            {
+                Assert.assertNotNull(rs.getTimestamp(1));
+                Assert.assertNotNull(rs.getTimestamp("ts"));
+                Assert.assertNotNull(rs.getByte(2));
+                Assert.assertNotNull(rs.getByte("level"));
+                Assert.assertNotNull(rs.getString(3));
+                Assert.assertNotNull(rs.getString("content"));
+                Assert.assertNotNull(rs.getString(4));
+                Assert.assertNotNull(rs.getString("ipaddr"));
+            }
             subscribe.close(false);
         } catch (SQLException e) {
             e.printStackTrace();

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBDatabaseMetaDataTest.java

@@ -7,9 +7,11 @@ import java.util.Properties;
 
 public class TSDBDatabaseMetaDataTest {
     private static final String host = "127.0.0.1";
+    private static final String url = "jdbc:TAOS://" + host + ":6030/?user=root&password=taosdata";
     private static Connection connection;
     private static TSDBDatabaseMetaData metaData;
 
+
     @Test
     public void unwrap() throws SQLException {
         TSDBDatabaseMetaData unwrap = metaData.unwrap(TSDBDatabaseMetaData.class);
@@ -33,7 +35,7 @@ public class TSDBDatabaseMetaDataTest {
 
     @Test
     public void getURL() throws SQLException {
-        Assert.assertEquals("jdbc:TAOS://" + host + ":6030/?user=root&password=taosdata", metaData.getURL());
+        Assert.assertEquals(url, metaData.getURL());
     }
 
     @Test
@@ -627,17 +629,32 @@ public class TSDBDatabaseMetaDataTest {
 
     @Test
     public void getTables() throws SQLException {
-        System.out.println("****************************************************");
-        ResultSet tables = metaData.getTables("log", "", null, null);
-        ResultSetMetaData metaData = tables.getMetaData();
-        while (tables.next()) {
-            System.out.print(metaData.getColumnLabel(1) + ":" + tables.getString(1) + "\t");
-            System.out.print(metaData.getColumnLabel(3) + ":" + tables.getString(3) + "\t");
-            System.out.print(metaData.getColumnLabel(4) + ":" + tables.getString(4) + "\t");
-            System.out.print(metaData.getColumnLabel(5) + ":" + tables.getString(5) + "\n");
+        ResultSet rs = metaData.getTables("log", "", null, null);
+        ResultSetMetaData meta = rs.getMetaData();
+        Assert.assertNotNull(rs);
+        rs.next();
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", rs.getString(1));
+            Assert.assertEquals("log", rs.getString("TABLE_CAT"));
+            // TABLE_SCHEM
+            Assert.assertEquals("TABLE_SCHEM", meta.getColumnLabel(2));
+            Assert.assertEquals(null, rs.getString(2));
+            Assert.assertEquals(null, rs.getString("TABLE_SCHEM"));
+            // TABLE_NAME
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertNotNull(rs.getString(3));
+            Assert.assertNotNull(rs.getString("TABLE_NAME"));
+            // TABLE_TYPE
+            Assert.assertEquals("TABLE_TYPE", meta.getColumnLabel(4));
+            Assert.assertEquals("TABLE", rs.getString(4));
+            Assert.assertEquals("TABLE", rs.getString("TABLE_TYPE"));
+            // REMARKS
+            Assert.assertEquals("REMARKS", meta.getColumnLabel(5));
+            Assert.assertEquals("", rs.getString(5));
+            Assert.assertEquals("", rs.getString("REMARKS"));
         }
-        System.out.println();
-        Assert.assertNotNull(tables);
     }
 
     @Test
@@ -647,46 +664,130 @@ public class TSDBDatabaseMetaDataTest {
 
     @Test
     public void getCatalogs() throws SQLException {
-        System.out.println("****************************************************");
-
-        ResultSet catalogs = metaData.getCatalogs();
-        ResultSetMetaData meta = catalogs.getMetaData();
-        while (catalogs.next()) {
-            for (int i = 1; i <= meta.getColumnCount(); i++) {
-                System.out.print(meta.getColumnLabel(i) + ": " + catalogs.getString(i));
-            }
-            System.out.println();
+        ResultSet rs = metaData.getCatalogs();
+        ResultSetMetaData meta = rs.getMetaData();
+        rs.next();
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertNotNull(rs.getString(1));
+            Assert.assertNotNull(rs.getString("TABLE_CAT"));
         }
     }
 
     @Test
     public void getTableTypes() throws SQLException {
-        System.out.println("****************************************************");
-
         ResultSet tableTypes = metaData.getTableTypes();
-        while (tableTypes.next()) {
-            System.out.println(tableTypes.getString("TABLE_TYPE"));
+        tableTypes.next();
+        // tableTypes: table
+        {
+            Assert.assertEquals("TABLE", tableTypes.getString(1));
+            Assert.assertEquals("TABLE", tableTypes.getString("TABLE_TYPE"));
+        }
+        tableTypes.next();
+        // tableTypes: stable
+        {
+            Assert.assertEquals("STABLE", tableTypes.getString(1));
+            Assert.assertEquals("STABLE", tableTypes.getString("TABLE_TYPE"));
         }
-        Assert.assertNotNull(metaData.getTableTypes());
     }
 
     @Test
     public void getColumns() throws SQLException {
-        System.out.println("****************************************************");
-
+        // when
         ResultSet columns = metaData.getColumns("log", "", "dn", "");
+        // then
         ResultSetMetaData meta = columns.getMetaData();
-        while (columns.next()) {
-            System.out.print(meta.getColumnLabel(1) + ": " + columns.getString(1) + "\t");
-            System.out.print(meta.getColumnLabel(3) + ": " + columns.getString(3) + "\t");
-            System.out.print(meta.getColumnLabel(4) + ": " + columns.getString(4) + "\t");
-            System.out.print(meta.getColumnLabel(5) + ": " + columns.getString(5) + "\t");
-            System.out.print(meta.getColumnLabel(6) + ": " + columns.getString(6) + "\t");
-            System.out.print(meta.getColumnLabel(7) + ": " + columns.getString(7) + "\t");
-            System.out.print(meta.getColumnLabel(9) + ": " + columns.getString(9) + "\t");
-            System.out.print(meta.getColumnLabel(10) + ": " + columns.getString(10) + "\t");
-            System.out.print(meta.getColumnLabel(11) + ": " + columns.getString(11) + "\n");
-            System.out.print(meta.getColumnLabel(12) + ": " + columns.getString(12) + "\n");
+        columns.next();
+        // column: 1
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", columns.getString(1));
+            Assert.assertEquals("log", columns.getString("TABLE_CAT"));
+            // TABLE_NAME
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertEquals("dn", columns.getString(3));
+            Assert.assertEquals("dn", columns.getString("TABLE_NAME"));
+            // COLUMN_NAME
+            Assert.assertEquals("COLUMN_NAME", meta.getColumnLabel(4));
+            Assert.assertEquals("ts", columns.getString(4));
+            Assert.assertEquals("ts", columns.getString("COLUMN_NAME"));
+            // DATA_TYPE
+            Assert.assertEquals("DATA_TYPE", meta.getColumnLabel(5));
+            Assert.assertEquals(Types.TIMESTAMP, columns.getInt(5));
+            Assert.assertEquals(Types.TIMESTAMP, columns.getInt("DATA_TYPE"));
+            // TYPE_NAME
+            Assert.assertEquals("TYPE_NAME", meta.getColumnLabel(6));
+            Assert.assertEquals("TIMESTAMP", columns.getString(6));
+            Assert.assertEquals("TIMESTAMP", columns.getString("TYPE_NAME"));
+            // COLUMN_SIZE
+            Assert.assertEquals("COLUMN_SIZE", meta.getColumnLabel(7));
+            Assert.assertEquals(26, columns.getInt(7));
+            Assert.assertEquals(26, columns.getInt("COLUMN_SIZE"));
+            // DECIMAL_DIGITS
+            Assert.assertEquals("DECIMAL_DIGITS", meta.getColumnLabel(9));
+            Assert.assertEquals(Integer.MIN_VALUE, columns.getInt(9));
+            Assert.assertEquals(Integer.MIN_VALUE, columns.getInt("DECIMAL_DIGITS"));
+            Assert.assertEquals(null, columns.getString(9));
+            Assert.assertEquals(null, columns.getString("DECIMAL_DIGITS"));
+            // NUM_PREC_RADIX
+            Assert.assertEquals("NUM_PREC_RADIX", meta.getColumnLabel(10));
+            Assert.assertEquals(10, columns.getInt(10));
+            Assert.assertEquals(10, columns.getInt("NUM_PREC_RADIX"));
+            // NULLABLE
+            Assert.assertEquals("NULLABLE", meta.getColumnLabel(11));
+            Assert.assertEquals(DatabaseMetaData.columnNoNulls, columns.getInt(11));
+            Assert.assertEquals(DatabaseMetaData.columnNoNulls, columns.getInt("NULLABLE"));
+            // REMARKS
+            Assert.assertEquals("REMARKS", meta.getColumnLabel(12));
+            Assert.assertEquals(null, columns.getString(12));
+            Assert.assertEquals(null, columns.getString("REMARKS"));
+        }
+        columns.next();
+        // column: 2
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", columns.getString(1));
+            Assert.assertEquals("log", columns.getString("TABLE_CAT"));
+            // TABLE_NAME
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertEquals("dn", columns.getString(3));
+            Assert.assertEquals("dn", columns.getString("TABLE_NAME"));
+            // COLUMN_NAME
+            Assert.assertEquals("COLUMN_NAME", meta.getColumnLabel(4));
+            Assert.assertEquals("cpu_taosd", columns.getString(4));
+            Assert.assertEquals("cpu_taosd", columns.getString("COLUMN_NAME"));
+            // DATA_TYPE
+            Assert.assertEquals("DATA_TYPE", meta.getColumnLabel(5));
+            Assert.assertEquals(Types.FLOAT, columns.getInt(5));
+            Assert.assertEquals(Types.FLOAT, columns.getInt("DATA_TYPE"));
+            // TYPE_NAME
+            Assert.assertEquals("TYPE_NAME", meta.getColumnLabel(6));
+            Assert.assertEquals("FLOAT", columns.getString(6));
+            Assert.assertEquals("FLOAT", columns.getString("TYPE_NAME"));
+            // COLUMN_SIZE
+            Assert.assertEquals("COLUMN_SIZE", meta.getColumnLabel(7));
+            Assert.assertEquals(12, columns.getInt(7));
+            Assert.assertEquals(12, columns.getInt("COLUMN_SIZE"));
+            // DECIMAL_DIGITS
+            Assert.assertEquals("DECIMAL_DIGITS", meta.getColumnLabel(9));
+            Assert.assertEquals(Integer.MIN_VALUE, columns.getInt(9));
+            Assert.assertEquals(Integer.MIN_VALUE, columns.getInt("DECIMAL_DIGITS"));
+            Assert.assertEquals(null, columns.getString(9));
+            Assert.assertEquals(null, columns.getString("DECIMAL_DIGITS"));
+            // NUM_PREC_RADIX
+            Assert.assertEquals("NUM_PREC_RADIX", meta.getColumnLabel(10));
+            Assert.assertEquals(10, columns.getInt(10));
+            Assert.assertEquals(10, columns.getInt("NUM_PREC_RADIX"));
+            // NULLABLE
+            Assert.assertEquals("NULLABLE", meta.getColumnLabel(11));
+            Assert.assertEquals(DatabaseMetaData.columnNullable, columns.getInt(11));
+            Assert.assertEquals(DatabaseMetaData.columnNullable, columns.getInt("NULLABLE"));
+            // REMARKS
+            Assert.assertEquals("REMARKS", meta.getColumnLabel(12));
+            Assert.assertEquals(null, columns.getString(12));
         }
     }
 
@@ -712,17 +813,35 @@ public class TSDBDatabaseMetaDataTest {
 
     @Test
     public void getPrimaryKeys() throws SQLException {
-        System.out.println("****************************************************");
-
         ResultSet rs = metaData.getPrimaryKeys("log", "", "dn1");
-        while (rs.next()) {
-            System.out.println("TABLE_NAME: " + rs.getString("TABLE_NAME"));
-            System.out.println("COLUMN_NAME: " + rs.getString("COLUMN_NAME"));
-            System.out.println("KEY_SEQ: " + rs.getString("KEY_SEQ"));
-            System.out.println("PK_NAME: " + rs.getString("PK_NAME"));
+        ResultSetMetaData meta = rs.getMetaData();
+        rs.next();
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", rs.getString(1));
+            Assert.assertEquals("log", rs.getString("TABLE_CAT"));
+            // TABLE_SCHEM
+            Assert.assertEquals("TABLE_SCHEM", meta.getColumnLabel(2));
+            Assert.assertEquals(null, rs.getString(2));
+            Assert.assertEquals(null, rs.getString("TABLE_SCHEM"));
+            // TABLE_NAME
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertEquals("dn1", rs.getString(3));
+            Assert.assertEquals("dn1", rs.getString("TABLE_NAME"));
+            // COLUMN_NAME
+            Assert.assertEquals("COLUMN_NAME", meta.getColumnLabel(4));
+            Assert.assertEquals("ts", rs.getString(4));
+            Assert.assertEquals("ts", rs.getString("COLUMN_NAME"));
+            // KEY_SEQ
+            Assert.assertEquals("KEY_SEQ", meta.getColumnLabel(5));
+            Assert.assertEquals(1, rs.getShort(5));
+            Assert.assertEquals(1, rs.getShort("KEY_SEQ"));
+            // DATA_TYPE
+            Assert.assertEquals("PK_NAME", meta.getColumnLabel(6));
+            Assert.assertEquals("ts", rs.getString(6));
+            Assert.assertEquals("ts", rs.getString("PK_NAME"));
         }
-
-        Assert.assertNotNull(rs);
     }
 
     @Test
@@ -847,14 +966,27 @@ public class TSDBDatabaseMetaDataTest {
 
     @Test
     public void getSuperTables() throws SQLException {
-        System.out.println("****************************************************");
-
         ResultSet rs = metaData.getSuperTables("log", "", "dn1");
-        while (rs.next()) {
-            System.out.println("TABLE_NAME: " + rs.getString("TABLE_NAME"));
-            System.out.println("SUPERTABLE_NAME: " + rs.getString("SUPERTABLE_NAME"));
+        ResultSetMetaData meta = rs.getMetaData();
+        rs.next();
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", rs.getString(1));
+            Assert.assertEquals("log", rs.getString("TABLE_CAT"));
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_SCHEM", meta.getColumnLabel(2));
+            Assert.assertEquals(null, rs.getString(2));
+            Assert.assertEquals(null, rs.getString("TABLE_SCHEM"));
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertEquals("dn1", rs.getString(3));
+            Assert.assertEquals("dn1", rs.getString("TABLE_NAME"));
+            // TABLE_CAT
+            Assert.assertEquals("SUPERTABLE_NAME", meta.getColumnLabel(4));
+            Assert.assertEquals("dn", rs.getString(4));
+            Assert.assertEquals("dn", rs.getString("SUPERTABLE_NAME"));
         }
-        Assert.assertNotNull(rs);
     }
 
     @Test
@@ -951,15 +1083,12 @@ public class TSDBDatabaseMetaDataTest {
     @BeforeClass
     public static void beforeClass() {
         try {
-            Class.forName("com.taosdata.jdbc.TSDBDriver");
             Properties properties = new Properties();
             properties.setProperty(TSDBDriver.PROPERTY_KEY_CHARSET, "UTF-8");
             properties.setProperty(TSDBDriver.PROPERTY_KEY_LOCALE, "en_US.UTF-8");
             properties.setProperty(TSDBDriver.PROPERTY_KEY_TIME_ZONE, "UTC-8");
-            connection = DriverManager.getConnection("jdbc:TAOS://" + host + ":6030/?user=root&password=taosdata", properties);
+            connection = DriverManager.getConnection(url, properties);
             metaData = connection.getMetaData().unwrap(TSDBDatabaseMetaData.class);
-        } catch (ClassNotFoundException e) {
-            e.printStackTrace();
         } catch (SQLException e) {
             e.printStackTrace();
         }

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBJNIConnectorTest.java

@@ -45,9 +45,9 @@ public class TSDBJNIConnectorTest {
             rowData = new TSDBResultSetRowData(columnSize);
             // iterate resultSet
             for (int i = 0; next(connector, pSql); i++) {
-                System.out.println("col[" + i + "] size: " + rowData.getColSize());
-                rowData.getData().stream().forEach(col -> System.out.print(col + "\t"));
-                System.out.println();
+//                System.out.println("col[" + i + "] size: " + rowData.getColSize());
+//                rowData.getData().stream().forEach(col -> System.out.print(col + "\t"));
+//                System.out.println();
             }
             // close resultSet
             code = connector.freeResultSet(pSql);

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBParameterMetaDataTest.java

@@ -54,16 +54,17 @@ public class TSDBParameterMetaDataTest {
 
     @Test
     public void getPrecision() throws SQLException {
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(1));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(2));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(3));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(4));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(5));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(6));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(7));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(8));
-        Assert.assertEquals(5, parameterMetaData_insert.getPrecision(9));
-        Assert.assertEquals(5, parameterMetaData_insert.getPrecision(10));
+        //create table weather(ts timestamp, f1 int, f2 bigint, f3 float, f4 double, f5 smallint, f6 tinyint, f7 bool, f8 binary(64), f9 nchar(64))
+        Assert.assertEquals(TSDBConstants.TIMESTAMP_MS_PRECISION, parameterMetaData_insert.getPrecision(1));
+        Assert.assertEquals(TSDBConstants.INT_PRECISION, parameterMetaData_insert.getPrecision(2));
+        Assert.assertEquals(TSDBConstants.BIGINT_PRECISION, parameterMetaData_insert.getPrecision(3));
+        Assert.assertEquals(TSDBConstants.FLOAT_PRECISION, parameterMetaData_insert.getPrecision(4));
+        Assert.assertEquals(TSDBConstants.DOUBLE_PRECISION, parameterMetaData_insert.getPrecision(5));
+        Assert.assertEquals(TSDBConstants.SMALLINT_PRECISION, parameterMetaData_insert.getPrecision(6));
+        Assert.assertEquals(TSDBConstants.TINYINT_PRECISION, parameterMetaData_insert.getPrecision(7));
+        Assert.assertEquals(TSDBConstants.BOOLEAN_PRECISION, parameterMetaData_insert.getPrecision(8));
+        Assert.assertEquals("hello".getBytes().length, parameterMetaData_insert.getPrecision(9));
+        Assert.assertEquals("涛思数据".length(), parameterMetaData_insert.getPrecision(10));
     }
 
     @Test
@@ -71,8 +72,8 @@ public class TSDBParameterMetaDataTest {
         Assert.assertEquals(0, parameterMetaData_insert.getScale(1));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(2));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(3));
-        Assert.assertEquals(0, parameterMetaData_insert.getScale(4));
-        Assert.assertEquals(0, parameterMetaData_insert.getScale(5));
+        Assert.assertEquals(31, parameterMetaData_insert.getScale(4));
+        Assert.assertEquals(31, parameterMetaData_insert.getScale(5));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(6));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(7));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(8));
@@ -124,10 +125,16 @@ public class TSDBParameterMetaDataTest {
 
     @Test
     public void getParameterMode() throws SQLException {
-        for (int i = 1; i <= parameterMetaData_insert.getParameterCount(); i++) {
-            int parameterMode = parameterMetaData_insert.getParameterMode(i);
-            Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMode);
-        }
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(1));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(2));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(3));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(4));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(5));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(6));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(7));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(8));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(9));
+        Assert.assertEquals(ParameterMetaData.parameterModeUnknown, parameterMetaData_insert.getParameterMode(10));
     }
 
     @Test
@@ -144,7 +151,6 @@ public class TSDBParameterMetaDataTest {
     @BeforeClass
     public static void beforeClass() {
         try {
-            Class.forName("com.taosdata.jdbc.TSDBDriver");
             conn = DriverManager.getConnection("jdbc:TAOS://" + host + ":6030/?user=root&password=taosdata");
             try (Statement stmt = conn.createStatement()) {
                 stmt.execute("drop database if exists test_pstmt");
@@ -164,7 +170,7 @@ public class TSDBParameterMetaDataTest {
             pstmt_insert.setObject(7, Byte.MAX_VALUE);
             pstmt_insert.setObject(8, true);
             pstmt_insert.setObject(9, "hello".getBytes());
-            pstmt_insert.setObject(10, "Hello");
+            pstmt_insert.setObject(10, "涛思数据");
             parameterMetaData_insert = pstmt_insert.getParameterMetaData();
 
             pstmt_select = conn.prepareStatement(sql_select);
@@ -173,7 +179,7 @@ public class TSDBParameterMetaDataTest {
             pstmt_select.setInt(3, 0);
             parameterMetaData_select = pstmt_select.getParameterMetaData();
 
-        } catch (ClassNotFoundException | SQLException e) {
+        } catch (SQLException e) {
             e.printStackTrace();
         }
     }

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBPreparedStatementTest.java

 package com.taosdata.jdbc;
 
-import org.junit.AfterClass;
-import org.junit.Assert;
-import org.junit.BeforeClass;
-import org.junit.Test;
+import org.junit.*;
 
 import java.io.IOException;
-import java.io.Serializable;
+import java.math.BigDecimal;
 import java.sql.*;
+import java.util.ArrayList;
+import java.util.Random;
 
 public class TSDBPreparedStatementTest {
+
     private static final String host = "127.0.0.1";
     private static Connection conn;
     private static final String sql_insert = "insert into t1 values(?, ?, ?, ?, ?, ?, ?, ?, ?, ?)";
-    private static PreparedStatement pstmt_insert;
-    private static final String sql_select = "select * from t1 where ts > ? and ts <= ? and f1 >= ?";
-    private static PreparedStatement pstmt_select;
+    private static final String sql_select = "select * from t1 where ts >= ? and ts < ? and f1 >= ?";
+
+    private PreparedStatement pstmt_insert;
+    private PreparedStatement pstmt_select;
+    //create table weather(ts timestamp, f1 int, f2 bigint, f3 float, f4 double, f5 smallint, f6 tinyint, f7 bool, f8 binary(64), f9 nchar(64)) tags(loc nchar(64))
 
     @Test
     public void executeQuery() throws SQLException {
-        long end = System.currentTimeMillis();
-        long start = end - 1000 * 60 * 60;
+        // given
+        long ts = System.currentTimeMillis();
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
+        pstmt_insert.setInt(2, 2);
+        pstmt_insert.setLong(3, 3l);
+        pstmt_insert.setFloat(4, 3.14f);
+        pstmt_insert.setDouble(5, 3.1415);
+        pstmt_insert.setShort(6, (short) 6);
+        pstmt_insert.setByte(7, (byte) 7);
+        pstmt_insert.setBoolean(8, true);
+        pstmt_insert.setBytes(9, "abc".getBytes());
+        pstmt_insert.setString(10, "涛思数据");
+        pstmt_insert.executeUpdate();
+        long start = ts - 1000 * 60 * 60;
+        long end = ts + 1000 * 60 * 60;
         pstmt_select.setTimestamp(1, new Timestamp(start));
         pstmt_select.setTimestamp(2, new Timestamp(end));
         pstmt_select.setInt(3, 0);
 
+        // when
         ResultSet rs = pstmt_select.executeQuery();
-        Assert.assertNotNull(rs);
         ResultSetMetaData meta = rs.getMetaData();
-        while (rs.next()) {
-            for (int i = 1; i <= meta.getColumnCount(); i++) {
-                System.out.print(meta.getColumnLabel(i) + ": " + rs.getString(i) + "\t");
-            }
-            System.out.println();
+        rs.next();
+
+        // then
+        assertMetaData(meta);
+        {
+            Assert.assertNotNull(rs);
+            Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+            Assert.assertEquals(2, rs.getInt(2));
+            Assert.assertEquals(2, rs.getInt("f1"));
+            Assert.assertEquals(3l, rs.getLong(3));
+            Assert.assertEquals(3l, rs.getLong("f2"));
+            Assert.assertEquals(3.14f, rs.getFloat(4), 0.0);
+            Assert.assertEquals(3.14f, rs.getFloat("f3"), 0.0);
+            Assert.assertEquals(3.1415, rs.getDouble(5), 0.0);
+            Assert.assertEquals(3.1415, rs.getDouble("f4"), 0.0);
+            Assert.assertEquals((short) 6, rs.getShort(6));
+            Assert.assertEquals((short) 6, rs.getShort("f5"));
+            Assert.assertEquals((byte) 7, rs.getByte(7));
+            Assert.assertEquals((byte) 7, rs.getByte("f6"));
+            Assert.assertTrue(rs.getBoolean(8));
+            Assert.assertTrue(rs.getBoolean("f7"));
+            Assert.assertArrayEquals("abc".getBytes(), rs.getBytes(9));
+            Assert.assertArrayEquals("abc".getBytes(), rs.getBytes("f8"));
+            Assert.assertEquals("涛思数据", rs.getString(10));
+            Assert.assertEquals("涛思数据", rs.getString("f9"));
         }
     }
 
-    @Test
-    public void executeUpdate() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setFloat(4, 3.14f);
-        int result = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, result);
+    private void assertMetaData(ResultSetMetaData meta) throws SQLException {
+        Assert.assertEquals(10, meta.getColumnCount());
+        Assert.assertEquals("ts", meta.getColumnLabel(1));
+        Assert.assertEquals("f1", meta.getColumnLabel(2));
+        Assert.assertEquals("f2", meta.getColumnLabel(3));
+        Assert.assertEquals("f3", meta.getColumnLabel(4));
+        Assert.assertEquals("f4", meta.getColumnLabel(5));
+        Assert.assertEquals("f5", meta.getColumnLabel(6));
+        Assert.assertEquals("f6", meta.getColumnLabel(7));
+        Assert.assertEquals("f7", meta.getColumnLabel(8));
+        Assert.assertEquals("f8", meta.getColumnLabel(9));
+        Assert.assertEquals("f9", meta.getColumnLabel(10));
     }
 
     @Test
-    public void setNull() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    public void setNullForTimestamp() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(2, Types.INTEGER);
         int result = pstmt_insert.executeUpdate();
+
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
+    }
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    private void assertAllNullExceptTimestamp(ResultSet rs, long ts) throws SQLException {
+        Assert.assertNotNull(rs);
+        Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+        Assert.assertEquals(0, rs.getInt(2));
+        Assert.assertEquals(0, rs.getInt("f1"));
+        Assert.assertEquals(0, rs.getLong(3));
+        Assert.assertEquals(0, rs.getLong("f2"));
+        Assert.assertEquals(0, rs.getFloat(4), 0.0);
+        Assert.assertEquals(0, rs.getFloat("f3"), 0.0);
+        Assert.assertEquals(0, rs.getDouble(5), 0.0);
+        Assert.assertEquals(0, rs.getDouble("f4"), 0.0);
+        Assert.assertEquals(0, rs.getShort(6));
+        Assert.assertEquals(0, rs.getShort("f5"));
+        Assert.assertEquals(0, rs.getByte(7));
+        Assert.assertEquals(0, rs.getByte("f6"));
+        Assert.assertFalse(rs.getBoolean(8));
+        Assert.assertFalse(rs.getBoolean("f7"));
+        Assert.assertNull(rs.getBytes(9));
+        Assert.assertNull(rs.getBytes("f8"));
+        Assert.assertNull(rs.getString(10));
+        Assert.assertNull(rs.getString("f9"));
+    }
+
+    @Test
+    public void setNullForInteger() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(3, Types.BIGINT);
-        result = pstmt_insert.executeUpdate();
+        int result = pstmt_insert.executeUpdate();
+
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
+    }
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    @Test
+    public void setNullForFloat() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(4, Types.FLOAT);
-        result = pstmt_insert.executeUpdate();
+        int result = pstmt_insert.executeUpdate();
+
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
+    }
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    @Test
+    public void setNullForDouble() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(5, Types.DOUBLE);
-        result = pstmt_insert.executeUpdate();
+        int result = pstmt_insert.executeUpdate();
+
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
+    }
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    @Test
+    public void setNullForSmallInt() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(6, Types.SMALLINT);
-        result = pstmt_insert.executeUpdate();
+        int result = pstmt_insert.executeUpdate();
+
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
+    }
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    @Test
+    public void setNullForTinyInt() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(7, Types.TINYINT);
-        result = pstmt_insert.executeUpdate();
+        int result = pstmt_insert.executeUpdate();
+
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
+    }
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    @Test
+    public void setNullForBoolean() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(8, Types.BOOLEAN);
-        result = pstmt_insert.executeUpdate();
+        int result = pstmt_insert.executeUpdate();
+
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
+    }
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    @Test
+    public void setNullForBinary() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(9, Types.BINARY);
-        result = pstmt_insert.executeUpdate();
+        int result = pstmt_insert.executeUpdate();
+
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
+    }
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+    @Test
+    public void setNullForNchar() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setNull(10, Types.NCHAR);
-        result = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, result);
+        int result = pstmt_insert.executeUpdate();
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setNull(10, Types.OTHER);
-        result = pstmt_insert.executeUpdate();
+        // then
         Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            assertAllNullExceptTimestamp(rs, ts);
+        }
     }
-
+    
     @Test
     public void setBoolean() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setBoolean(8, true);
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertTrue(rs.getBoolean(8));
+                Assert.assertTrue(rs.getBoolean("f7"));
+            }
+        }
     }
 
     @Test
     public void setByte() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setByte(7, (byte) 0x001);
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertEquals((byte) 0x001, rs.getByte(7));
+                Assert.assertEquals((byte) 0x001, rs.getByte("f6"));
+            }
+        }
     }
 
     @Test
     public void setShort() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setShort(6, (short) 2);
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertEquals((short) 2, rs.getByte(6));
+                Assert.assertEquals((short) 2, rs.getByte("f5"));
+            }
+        }
     }
 
     @Test
     public void setInt() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setInt(2, 10086);
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertEquals(10086, rs.getInt(2));
+                Assert.assertEquals(10086, rs.getInt("f1"));
+            }
+        }
     }
 
     @Test
     public void setLong() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setLong(3, Long.MAX_VALUE);
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertEquals(Long.MAX_VALUE, rs.getLong(3));
+                Assert.assertEquals(Long.MAX_VALUE, rs.getLong("f2"));
+            }
+        }
     }
 
     @Test
     public void setFloat() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setFloat(4, 3.14f);
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertEquals(3.14f, rs.getFloat(4), 0.0f);
+                Assert.assertEquals(3.14f, rs.getFloat("f3"), 0.0f);
+            }
+        }
     }
 
     @Test
     public void setDouble() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setDouble(5, 3.14444);
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-    }
+        int result = pstmt_insert.executeUpdate();
 
-    @Test(expected = SQLFeatureNotSupportedException.class)
-    public void setBigDecimal() throws SQLException {
-        pstmt_insert.setBigDecimal(1, null);
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertEquals(3.14444, rs.getDouble(5), 0.0);
+                Assert.assertEquals(3.14444, rs.getDouble("f4"), 0.0);
+            }
+        }
     }
 
     @Test
-    public void setString() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setString(10, "aaaa");
-        boolean execute = pstmt_insert.execute();
-        Assert.assertFalse(execute);
+    public void setBigDecimal() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+        BigDecimal bigDecimal = new BigDecimal(3.14444);
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setString(10, new Person("john", 33, true).toString());
-        Assert.assertFalse(pstmt_insert.execute());
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
+        pstmt_insert.setBigDecimal(5, bigDecimal);
+        int result = pstmt_insert.executeUpdate();
 
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setString(10, new Person("john", 33, true).toString().replaceAll("'", "\""));
-        Assert.assertFalse(pstmt_insert.execute());
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertEquals(3.14444, rs.getDouble(5), 0.0);
+                Assert.assertEquals(3.14444, rs.getDouble("f4"), 0.0);
+            }
+        }
     }
 
-    class Person {
-        String name;
-        int age;
-        boolean sex;
+    @Test
+    public void setString() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+        String f9 = "{\"name\": \"john\", \"age\": 10, \"address\": \"192.168.1.100\"}";
 
-        public Person(String name, int age, boolean sex) {
-            this.name = name;
-            this.age = age;
-            this.sex = sex;
-        }
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
+        pstmt_insert.setString(10, f9);
+        int result = pstmt_insert.executeUpdate();
 
-        @Override
-        public String toString() {
-            return "Person{" +
-                    "name='" + name + '\'' +
-                    ", age=" + age +
-                    ", sex=" + sex +
-                    '}';
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertEquals(f9, rs.getString(10));
+                Assert.assertEquals(f9, rs.getString("f9"));
+            }
         }
     }
 
     @Test
     public void setBytes() throws SQLException, IOException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+        byte[] f8 = "{\"name\": \"john\", \"age\": 10, \"address\": \"192.168.1.100\"}".getBytes();
 
-//        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-//        ObjectOutputStream oos = new ObjectOutputStream(baos);
-//        oos.writeObject(new Person("john", 33, true));
-//        oos.flush();
-//        byte[] bytes = baos.toByteArray();
-//        pstmt_insert.setBytes(9, bytes);
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
+        pstmt_insert.setBytes(9, f8);
+        int result = pstmt_insert.executeUpdate();
 
-        pstmt_insert.setBytes(9, new Person("john", 33, true).toString().getBytes());
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+                Assert.assertArrayEquals(f8, rs.getBytes(9));
+                Assert.assertArrayEquals(f8, rs.getBytes("f8"));
+            }
+        }
     }
 
-    @Test(expected = SQLFeatureNotSupportedException.class)
+    @Test
     public void setDate() throws SQLException {
-        pstmt_insert.setDate(1, new Date(System.currentTimeMillis()));
+        // given
+        long ts = new java.util.Date().getTime();
+
+        // when
+        pstmt_insert.setDate(1, new Date(ts));
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+            }
+        }
     }
 
-    @Test(expected = SQLFeatureNotSupportedException.class)
+    @Test
     public void setTime() throws SQLException {
-        pstmt_insert.setTime(1, new Time(System.currentTimeMillis()));
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTime(1, new Time(ts));
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+            }
+        }
     }
 
     @Test
     public void setTimestamp() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
+        int result = pstmt_insert.executeUpdate();
+
+        // then
+        Assert.assertEquals(1, result);
+        try (Statement stmt = conn.createStatement()) {
+            ResultSet rs = stmt.executeQuery("select * from t1");
+            ResultSetMetaData meta = rs.getMetaData();
+            assertMetaData(meta);
+            rs.next();
+            {
+                Assert.assertNotNull(rs);
+                Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
+                Assert.assertEquals(ts, rs.getTimestamp("ts").getTime());
+            }
+        }
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)
@@ -238,72 +652,6 @@ public class TSDBPreparedStatementTest {
         pstmt_insert.setBinaryStream(1, null);
     }
 
-    @Test
-    public void clearParameters() throws SQLException {
-        pstmt_insert.clearParameters();
-    }
-
-    @Test
-    public void setObject() throws SQLException {
-        pstmt_insert.setObject(1, new Timestamp(System.currentTimeMillis()));
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(2, 111);
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(3, Long.MAX_VALUE);
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(4, 3.14159265354f);
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(5, Double.MAX_VALUE);
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(6, Short.MAX_VALUE);
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(7, Byte.MAX_VALUE);
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(8, true);
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(9, "hello".getBytes());
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        pstmt_insert.setObject(10, "Hello");
-        ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-    }
-
-    @Test
-    public void execute() throws SQLException {
-        pstmt_insert.setTimestamp(1, new Timestamp(System.currentTimeMillis()));
-        int ret = pstmt_insert.executeUpdate();
-        Assert.assertEquals(1, ret);
-
-        executeQuery();
-    }
-
     @Test(expected = SQLFeatureNotSupportedException.class)
     public void setCharacterStream() throws SQLException {
         pstmt_insert.setCharacterStream(1, null);
@@ -329,9 +677,17 @@ public class TSDBPreparedStatementTest {
         pstmt_insert.setArray(1, null);
     }
 
-    @Test(expected = SQLFeatureNotSupportedException.class)
+    @Test
     public void getMetaData() throws SQLException {
-        pstmt_insert.getMetaData();
+        // given
+        long ts = System.currentTimeMillis();
+
+        // when
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
+        ResultSetMetaData metaData = pstmt_insert.getMetaData();
+
+        // then
+        Assert.assertNull(metaData);
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)
@@ -341,9 +697,46 @@ public class TSDBPreparedStatementTest {
 
     @Test
     public void getParameterMetaData() throws SQLException {
+        // given
+        long ts = System.currentTimeMillis();
+        pstmt_insert.setTimestamp(1, new Timestamp(ts));
+        pstmt_insert.setInt(2, 2);
+        pstmt_insert.setLong(3, 3l);
+        pstmt_insert.setFloat(4, 3.14f);
+        pstmt_insert.setDouble(5, 3.1415);
+        pstmt_insert.setShort(6, (short) 6);
+        pstmt_insert.setByte(7, (byte) 7);
+        pstmt_insert.setBoolean(8, true);
+        pstmt_insert.setBytes(9, "abc".getBytes());
+        pstmt_insert.setString(10, "涛思数据");
+
+        // when
         ParameterMetaData parameterMetaData = pstmt_insert.getParameterMetaData();
+
+        // then
         Assert.assertNotNull(parameterMetaData);
-        //TODO: modify the test case
+        Assert.assertEquals(10, parameterMetaData.getParameterCount());
+        Assert.assertEquals(Types.TIMESTAMP, parameterMetaData.getParameterType(1));
+        Assert.assertEquals(Types.INTEGER, parameterMetaData.getParameterType(2));
+        Assert.assertEquals(Types.BIGINT, parameterMetaData.getParameterType(3));
+        Assert.assertEquals(Types.FLOAT, parameterMetaData.getParameterType(4));
+        Assert.assertEquals(Types.DOUBLE, parameterMetaData.getParameterType(5));
+        Assert.assertEquals(Types.SMALLINT, parameterMetaData.getParameterType(6));
+        Assert.assertEquals(Types.TINYINT, parameterMetaData.getParameterType(7));
+        Assert.assertEquals(Types.BOOLEAN, parameterMetaData.getParameterType(8));
+        Assert.assertEquals(Types.BINARY, parameterMetaData.getParameterType(9));
+        Assert.assertEquals(Types.NCHAR, parameterMetaData.getParameterType(10));
+
+        Assert.assertEquals("TIMESTAMP", parameterMetaData.getParameterTypeName(1));
+        Assert.assertEquals("INT", parameterMetaData.getParameterTypeName(2));
+        Assert.assertEquals("BIGINT", parameterMetaData.getParameterTypeName(3));
+        Assert.assertEquals("FLOAT", parameterMetaData.getParameterTypeName(4));
+        Assert.assertEquals("DOUBLE", parameterMetaData.getParameterTypeName(5));
+        Assert.assertEquals("SMALLINT", parameterMetaData.getParameterTypeName(6));
+        Assert.assertEquals("TINYINT", parameterMetaData.getParameterTypeName(7));
+        Assert.assertEquals("BOOL", parameterMetaData.getParameterTypeName(8));
+        Assert.assertEquals("BINARY", parameterMetaData.getParameterTypeName(9));
+        Assert.assertEquals("NCHAR", parameterMetaData.getParameterTypeName(10));
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)
@@ -351,9 +744,9 @@ public class TSDBPreparedStatementTest {
         pstmt_insert.setRowId(1, null);
     }
 
-    @Test(expected = SQLFeatureNotSupportedException.class)
+    @Test
     public void setNString() throws SQLException {
-        pstmt_insert.setNString(1, null);
+        setString();
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)
@@ -371,22 +764,45 @@ public class TSDBPreparedStatementTest {
         pstmt_insert.setSQLXML(1, null);
     }
 
+    @Before
+    public void before() {
+        try {
+            Statement stmt = conn.createStatement();
+            stmt.execute("drop table if exists weather");
+            stmt.execute("create table if not exists weather(ts timestamp, f1 int, f2 bigint, f3 float, f4 double, f5 smallint, f6 tinyint, f7 bool, f8 binary(64), f9 nchar(64)) tags(loc nchar(64))");
+            stmt.execute("create table if not exists t1 using weather tags('beijing')");
+            stmt.close();
+
+            pstmt_insert = conn.prepareStatement(sql_insert);
+            pstmt_select = conn.prepareStatement(sql_select);
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+    }
+
+    @After
+    public void after() {
+        try {
+            if (pstmt_insert != null)
+                pstmt_insert.close();
+            if (pstmt_select != null)
+                pstmt_select.close();
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+
+    }
 
     @BeforeClass
     public static void beforeClass() {
         try {
-            Class.forName("com.taosdata.jdbc.TSDBDriver");
             conn = DriverManager.getConnection("jdbc:TAOS://" + host + ":6030/?user=root&password=taosdata");
             try (Statement stmt = conn.createStatement()) {
                 stmt.execute("drop database if exists test_pstmt_jni");
                 stmt.execute("create database if not exists test_pstmt_jni");
                 stmt.execute("use test_pstmt_jni");
-                stmt.execute("create table weather(ts timestamp, f1 int, f2 bigint, f3 float, f4 double, f5 smallint, f6 tinyint, f7 bool, f8 binary(64), f9 nchar(64)) tags(loc nchar(64))");
-                stmt.execute("create table t1 using weather tags('beijing')");
             }
-            pstmt_insert = conn.prepareStatement(sql_insert);
-            pstmt_select = conn.prepareStatement(sql_select);
-        } catch (ClassNotFoundException | SQLException e) {
+        } catch (SQLException e) {
             e.printStackTrace();
         }
     }
@@ -394,10 +810,6 @@ public class TSDBPreparedStatementTest {
     @AfterClass
     public static void afterClass() {
         try {
-            if (pstmt_insert != null)
-                pstmt_insert.close();
-            if (pstmt_select != null)
-                pstmt_select.close();
             if (conn != null)
                 conn.close();
         } catch (SQLException e) {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBResultSetTest.java

@@ -3,7 +3,6 @@ package com.taosdata.jdbc;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
 import com.google.common.primitives.Shorts;
-import com.taosdata.jdbc.rs.RestfulResultSet;
 import org.junit.AfterClass;
 import org.junit.Assert;
 import org.junit.BeforeClass;
@@ -15,6 +14,7 @@ import java.math.BigDecimal;
 import java.sql.*;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
+import java.util.Arrays;
 
 public class TSDBResultSetTest {
 
@@ -134,7 +134,7 @@ public class TSDBResultSetTest {
         Assert.assertEquals(3.1415926, Double.valueOf(new String(f5)), 0.000000f);
 
         byte[] f6 = rs.getBytes("f6");
-        Assert.assertEquals("abc", new String(f6));
+        Assert.assertTrue(Arrays.equals("abc".getBytes(), f6));
 
         byte[] f7 = rs.getBytes("f7");
         Assert.assertEquals((short) 10, Shorts.fromByteArray(f7));
@@ -177,7 +177,8 @@ public class TSDBResultSetTest {
         rs.getAsciiStream("f1");
     }
 
-    @Test(expected = SQLFeatureNotSupportedException.class)
+    @SuppressWarnings("deprecation")
+	@Test(expected = SQLFeatureNotSupportedException.class)
     public void getUnicodeStream() throws SQLException {
         rs.getUnicodeStream("f1");
     }
@@ -326,7 +327,7 @@ public class TSDBResultSetTest {
 
     @Test(expected = SQLFeatureNotSupportedException.class)
     public void getRow() throws SQLException {
-        int row = rs.getRow();
+        rs.getRow();
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)
@@ -405,12 +406,12 @@ public class TSDBResultSetTest {
 
     @Test(expected = SQLFeatureNotSupportedException.class)
     public void updateByte() throws SQLException {
-        rs.updateByte(1, new Byte("0"));
+        rs.updateByte(1, (byte) 0);
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)
     public void updateShort() throws SQLException {
-        rs.updateShort(1, new Short("0"));
+        rs.updateShort(1, (short) 0);
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)
@@ -646,7 +647,6 @@ public class TSDBResultSetTest {
     @BeforeClass
     public static void beforeClass() {
         try {
-            Class.forName("com.taosdata.jdbc.TSDBDriver");
             conn = DriverManager.getConnection("jdbc:TAOS://" + host + ":6030/?user=root&password=taosdata");
             stmt = conn.createStatement();
             stmt.execute("create database if not exists restful_test");
@@ -656,10 +656,9 @@ public class TSDBResultSetTest {
             stmt.execute("insert into restful_test.weather values('2021-01-01 00:00:00.000', 1, 100, 3.1415, 3.1415926, 'abc', 10, 10, true, '涛思数据')");
             rs = stmt.executeQuery("select * from restful_test.weather");
             rs.next();
-        } catch (ClassNotFoundException | SQLException e) {
+        } catch (SQLException e) {
             e.printStackTrace();
         }
-
     }
 
     @AfterClass

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBStatementTest.java

@@ -387,15 +387,12 @@ public class TSDBStatementTest {
     @BeforeClass
     public static void beforeClass() {
         try {
-            Class.forName("com.taosdata.jdbc.TSDBDriver");
             Properties properties = new Properties();
             properties.setProperty(TSDBDriver.PROPERTY_KEY_CHARSET, "UTF-8");
             properties.setProperty(TSDBDriver.PROPERTY_KEY_LOCALE, "en_US.UTF-8");
             properties.setProperty(TSDBDriver.PROPERTY_KEY_TIME_ZONE, "UTC-8");
             conn = DriverManager.getConnection("jdbc:TAOS://" + host + ":6030/?user=root&password=taosdata", properties);
             stmt = conn.createStatement();
-        } catch (ClassNotFoundException e) {
-            e.printStackTrace();
         } catch (SQLException e) {
             e.printStackTrace();
         }

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/InsertSpecialCharacterJniTest.java

@@ -345,6 +345,7 @@ public class InsertSpecialCharacterJniTest {
         }
     }
 
+
     @Test
     public void testCase12() throws SQLException {
         final long now = System.currentTimeMillis();

src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulDatabaseMetaDataTest.java

@@ -10,6 +10,7 @@ import java.sql.*;
 import java.util.Properties;
 
 public class RestfulDatabaseMetaDataTest {
+
     private static final String host = "127.0.0.1";
     private static final String url = "jdbc:TAOS-RS://" + host + ":6041/?user=root&password=taosdata";
     private static Connection connection;
@@ -632,17 +633,32 @@ public class RestfulDatabaseMetaDataTest {
 
     @Test
     public void getTables() throws SQLException {
-        System.out.println("****************************************************");
-        ResultSet tables = metaData.getTables("log", "", null, null);
-        ResultSetMetaData metaData = tables.getMetaData();
-        while (tables.next()) {
-            System.out.print(metaData.getColumnLabel(1) + ":" + tables.getString(1) + "\t");
-            System.out.print(metaData.getColumnLabel(3) + ":" + tables.getString(3) + "\t");
-            System.out.print(metaData.getColumnLabel(4) + ":" + tables.getString(4) + "\t");
-            System.out.print(metaData.getColumnLabel(5) + ":" + tables.getString(5) + "\n");
+        ResultSet rs = metaData.getTables("log", "", null, null);
+        ResultSetMetaData meta = rs.getMetaData();
+        Assert.assertNotNull(rs);
+        rs.next();
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", rs.getString(1));
+            Assert.assertEquals("log", rs.getString("TABLE_CAT"));
+            // TABLE_SCHEM
+            Assert.assertEquals("TABLE_SCHEM", meta.getColumnLabel(2));
+            Assert.assertEquals(null, rs.getString(2));
+            Assert.assertEquals(null, rs.getString("TABLE_SCHEM"));
+            // TABLE_NAME
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertNotNull(rs.getString(3));
+            Assert.assertNotNull(rs.getString("TABLE_NAME"));
+            // TABLE_TYPE
+            Assert.assertEquals("TABLE_TYPE", meta.getColumnLabel(4));
+            Assert.assertEquals("TABLE", rs.getString(4));
+            Assert.assertEquals("TABLE", rs.getString("TABLE_TYPE"));
+            // REMARKS
+            Assert.assertEquals("REMARKS", meta.getColumnLabel(5));
+            Assert.assertEquals("", rs.getString(5));
+            Assert.assertEquals("", rs.getString("REMARKS"));
         }
-        System.out.println();
-        Assert.assertNotNull(tables);
     }
 
     @Test
@@ -652,46 +668,130 @@ public class RestfulDatabaseMetaDataTest {
 
     @Test
     public void getCatalogs() throws SQLException {
-        System.out.println("****************************************************");
-
-        ResultSet catalogs = metaData.getCatalogs();
-        ResultSetMetaData meta = catalogs.getMetaData();
-        while (catalogs.next()) {
-            for (int i = 1; i <= meta.getColumnCount(); i++) {
-                System.out.print(meta.getColumnLabel(i) + ": " + catalogs.getString(i));
-            }
-            System.out.println();
+        ResultSet rs = metaData.getCatalogs();
+        ResultSetMetaData meta = rs.getMetaData();
+        rs.next();
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertNotNull(rs.getString(1));
+            Assert.assertNotNull(rs.getString("TABLE_CAT"));
         }
     }
 
     @Test
     public void getTableTypes() throws SQLException {
-        System.out.println("****************************************************");
-
         ResultSet tableTypes = metaData.getTableTypes();
-        while (tableTypes.next()) {
-            System.out.println(tableTypes.getString("TABLE_TYPE"));
+        tableTypes.next();
+        // tableTypes: table
+        {
+            Assert.assertEquals("TABLE", tableTypes.getString(1));
+            Assert.assertEquals("TABLE", tableTypes.getString("TABLE_TYPE"));
+        }
+        tableTypes.next();
+        // tableTypes: stable
+        {
+            Assert.assertEquals("STABLE", tableTypes.getString(1));
+            Assert.assertEquals("STABLE", tableTypes.getString("TABLE_TYPE"));
         }
-        Assert.assertNotNull(metaData.getTableTypes());
     }
 
     @Test
     public void getColumns() throws SQLException {
-        System.out.println("****************************************************");
-
+        // when
         ResultSet columns = metaData.getColumns("log", "", "dn", "");
+        // then
         ResultSetMetaData meta = columns.getMetaData();
-        while (columns.next()) {
-            System.out.print(meta.getColumnLabel(1) + ": " + columns.getString(1) + "\t");
-            System.out.print(meta.getColumnLabel(3) + ": " + columns.getString(3) + "\t");
-            System.out.print(meta.getColumnLabel(4) + ": " + columns.getString(4) + "\t");
-            System.out.print(meta.getColumnLabel(5) + ": " + columns.getString(5) + "\t");
-            System.out.print(meta.getColumnLabel(6) + ": " + columns.getString(6) + "\t");
-            System.out.print(meta.getColumnLabel(7) + ": " + columns.getString(7) + "\t");
-            System.out.print(meta.getColumnLabel(9) + ": " + columns.getString(9) + "\t");
-            System.out.print(meta.getColumnLabel(10) + ": " + columns.getString(10) + "\t");
-            System.out.print(meta.getColumnLabel(11) + ": " + columns.getString(11) + "\n");
-            System.out.print(meta.getColumnLabel(12) + ": " + columns.getString(12) + "\n");
+        columns.next();
+        // column: 1
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", columns.getString(1));
+            Assert.assertEquals("log", columns.getString("TABLE_CAT"));
+            // TABLE_NAME
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertEquals("dn", columns.getString(3));
+            Assert.assertEquals("dn", columns.getString("TABLE_NAME"));
+            // COLUMN_NAME
+            Assert.assertEquals("COLUMN_NAME", meta.getColumnLabel(4));
+            Assert.assertEquals("ts", columns.getString(4));
+            Assert.assertEquals("ts", columns.getString("COLUMN_NAME"));
+            // DATA_TYPE
+            Assert.assertEquals("DATA_TYPE", meta.getColumnLabel(5));
+            Assert.assertEquals(Types.TIMESTAMP, columns.getInt(5));
+            Assert.assertEquals(Types.TIMESTAMP, columns.getInt("DATA_TYPE"));
+            // TYPE_NAME
+            Assert.assertEquals("TYPE_NAME", meta.getColumnLabel(6));
+            Assert.assertEquals("TIMESTAMP", columns.getString(6));
+            Assert.assertEquals("TIMESTAMP", columns.getString("TYPE_NAME"));
+            // COLUMN_SIZE
+            Assert.assertEquals("COLUMN_SIZE", meta.getColumnLabel(7));
+            Assert.assertEquals(26, columns.getInt(7));
+            Assert.assertEquals(26, columns.getInt("COLUMN_SIZE"));
+            // DECIMAL_DIGITS
+            Assert.assertEquals("DECIMAL_DIGITS", meta.getColumnLabel(9));
+            Assert.assertEquals(Integer.MIN_VALUE, columns.getInt(9));
+            Assert.assertEquals(Integer.MIN_VALUE, columns.getInt("DECIMAL_DIGITS"));
+            Assert.assertEquals(null, columns.getString(9));
+            Assert.assertEquals(null, columns.getString("DECIMAL_DIGITS"));
+            // NUM_PREC_RADIX
+            Assert.assertEquals("NUM_PREC_RADIX", meta.getColumnLabel(10));
+            Assert.assertEquals(10, columns.getInt(10));
+            Assert.assertEquals(10, columns.getInt("NUM_PREC_RADIX"));
+            // NULLABLE
+            Assert.assertEquals("NULLABLE", meta.getColumnLabel(11));
+            Assert.assertEquals(DatabaseMetaData.columnNoNulls, columns.getInt(11));
+            Assert.assertEquals(DatabaseMetaData.columnNoNulls, columns.getInt("NULLABLE"));
+            // REMARKS
+            Assert.assertEquals("REMARKS", meta.getColumnLabel(12));
+            Assert.assertEquals(null, columns.getString(12));
+            Assert.assertEquals(null, columns.getString("REMARKS"));
+        }
+        columns.next();
+        // column: 2
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", columns.getString(1));
+            Assert.assertEquals("log", columns.getString("TABLE_CAT"));
+            // TABLE_NAME
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertEquals("dn", columns.getString(3));
+            Assert.assertEquals("dn", columns.getString("TABLE_NAME"));
+            // COLUMN_NAME
+            Assert.assertEquals("COLUMN_NAME", meta.getColumnLabel(4));
+            Assert.assertEquals("cpu_taosd", columns.getString(4));
+            Assert.assertEquals("cpu_taosd", columns.getString("COLUMN_NAME"));
+            // DATA_TYPE
+            Assert.assertEquals("DATA_TYPE", meta.getColumnLabel(5));
+            Assert.assertEquals(Types.FLOAT, columns.getInt(5));
+            Assert.assertEquals(Types.FLOAT, columns.getInt("DATA_TYPE"));
+            // TYPE_NAME
+            Assert.assertEquals("TYPE_NAME", meta.getColumnLabel(6));
+            Assert.assertEquals("FLOAT", columns.getString(6));
+            Assert.assertEquals("FLOAT", columns.getString("TYPE_NAME"));
+            // COLUMN_SIZE
+            Assert.assertEquals("COLUMN_SIZE", meta.getColumnLabel(7));
+            Assert.assertEquals(12, columns.getInt(7));
+            Assert.assertEquals(12, columns.getInt("COLUMN_SIZE"));
+            // DECIMAL_DIGITS
+            Assert.assertEquals("DECIMAL_DIGITS", meta.getColumnLabel(9));
+            Assert.assertEquals(Integer.MIN_VALUE, columns.getInt(9));
+            Assert.assertEquals(Integer.MIN_VALUE, columns.getInt("DECIMAL_DIGITS"));
+            Assert.assertEquals(null, columns.getString(9));
+            Assert.assertEquals(null, columns.getString("DECIMAL_DIGITS"));
+            // NUM_PREC_RADIX
+            Assert.assertEquals("NUM_PREC_RADIX", meta.getColumnLabel(10));
+            Assert.assertEquals(10, columns.getInt(10));
+            Assert.assertEquals(10, columns.getInt("NUM_PREC_RADIX"));
+            // NULLABLE
+            Assert.assertEquals("NULLABLE", meta.getColumnLabel(11));
+            Assert.assertEquals(DatabaseMetaData.columnNullable, columns.getInt(11));
+            Assert.assertEquals(DatabaseMetaData.columnNullable, columns.getInt("NULLABLE"));
+            // REMARKS
+            Assert.assertEquals("REMARKS", meta.getColumnLabel(12));
+            Assert.assertEquals(null, columns.getString(12));
         }
     }
 
@@ -717,17 +817,35 @@ public class RestfulDatabaseMetaDataTest {
 
     @Test
     public void getPrimaryKeys() throws SQLException {
-        System.out.println("****************************************************");
-
         ResultSet rs = metaData.getPrimaryKeys("log", "", "dn1");
-        while (rs.next()) {
-            System.out.println("TABLE_NAME: " + rs.getString("TABLE_NAME"));
-            System.out.println("COLUMN_NAME: " + rs.getString("COLUMN_NAME"));
-            System.out.println("KEY_SEQ: " + rs.getString("KEY_SEQ"));
-            System.out.println("PK_NAME: " + rs.getString("PK_NAME"));
+        ResultSetMetaData meta = rs.getMetaData();
+        rs.next();
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", rs.getString(1));
+            Assert.assertEquals("log", rs.getString("TABLE_CAT"));
+            // TABLE_SCHEM
+            Assert.assertEquals("TABLE_SCHEM", meta.getColumnLabel(2));
+            Assert.assertEquals(null, rs.getString(2));
+            Assert.assertEquals(null, rs.getString("TABLE_SCHEM"));
+            // TABLE_NAME
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertEquals("dn1", rs.getString(3));
+            Assert.assertEquals("dn1", rs.getString("TABLE_NAME"));
+            // COLUMN_NAME
+            Assert.assertEquals("COLUMN_NAME", meta.getColumnLabel(4));
+            Assert.assertEquals("ts", rs.getString(4));
+            Assert.assertEquals("ts", rs.getString("COLUMN_NAME"));
+            // KEY_SEQ
+            Assert.assertEquals("KEY_SEQ", meta.getColumnLabel(5));
+            Assert.assertEquals(1, rs.getShort(5));
+            Assert.assertEquals(1, rs.getShort("KEY_SEQ"));
+            // DATA_TYPE
+            Assert.assertEquals("PK_NAME", meta.getColumnLabel(6));
+            Assert.assertEquals("ts", rs.getString(6));
+            Assert.assertEquals("ts", rs.getString("PK_NAME"));
         }
-
-        Assert.assertNotNull(rs);
     }
 
     @Test
@@ -852,14 +970,27 @@ public class RestfulDatabaseMetaDataTest {
 
     @Test
     public void getSuperTables() throws SQLException {
-        System.out.println("****************************************************");
-
         ResultSet rs = metaData.getSuperTables("log", "", "dn1");
-        while (rs.next()) {
-            System.out.println("TABLE_NAME: " + rs.getString("TABLE_NAME"));
-            System.out.println("SUPERTABLE_NAME: " + rs.getString("SUPERTABLE_NAME"));
+        ResultSetMetaData meta = rs.getMetaData();
+        rs.next();
+        {
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_CAT", meta.getColumnLabel(1));
+            Assert.assertEquals("log", rs.getString(1));
+            Assert.assertEquals("log", rs.getString("TABLE_CAT"));
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_SCHEM", meta.getColumnLabel(2));
+            Assert.assertEquals(null, rs.getString(2));
+            Assert.assertEquals(null, rs.getString("TABLE_SCHEM"));
+            // TABLE_CAT
+            Assert.assertEquals("TABLE_NAME", meta.getColumnLabel(3));
+            Assert.assertEquals("dn1", rs.getString(3));
+            Assert.assertEquals("dn1", rs.getString("TABLE_NAME"));
+            // TABLE_CAT
+            Assert.assertEquals("SUPERTABLE_NAME", meta.getColumnLabel(4));
+            Assert.assertEquals("dn", rs.getString(4));
+            Assert.assertEquals("dn", rs.getString("SUPERTABLE_NAME"));
         }
-        Assert.assertNotNull(rs);
     }
 
     @Test

src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulParameterMetaDataTest.java

@@ -54,16 +54,17 @@ public class RestfulParameterMetaDataTest {
 
     @Test
     public void getPrecision() throws SQLException {
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(1));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(2));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(3));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(4));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(5));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(6));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(7));
-        Assert.assertEquals(0, parameterMetaData_insert.getPrecision(8));
-        Assert.assertEquals(5, parameterMetaData_insert.getPrecision(9));
-        Assert.assertEquals(5, parameterMetaData_insert.getPrecision(10));
+        //create table weather(ts timestamp, f1 int, f2 bigint, f3 float, f4 double, f5 smallint, f6 tinyint, f7 bool, f8 binary(64), f9 nchar(64))
+        Assert.assertEquals(TSDBConstants.TIMESTAMP_MS_PRECISION, parameterMetaData_insert.getPrecision(1));
+        Assert.assertEquals(TSDBConstants.INT_PRECISION, parameterMetaData_insert.getPrecision(2));
+        Assert.assertEquals(TSDBConstants.BIGINT_PRECISION, parameterMetaData_insert.getPrecision(3));
+        Assert.assertEquals(TSDBConstants.FLOAT_PRECISION, parameterMetaData_insert.getPrecision(4));
+        Assert.assertEquals(TSDBConstants.DOUBLE_PRECISION, parameterMetaData_insert.getPrecision(5));
+        Assert.assertEquals(TSDBConstants.SMALLINT_PRECISION, parameterMetaData_insert.getPrecision(6));
+        Assert.assertEquals(TSDBConstants.TINYINT_PRECISION, parameterMetaData_insert.getPrecision(7));
+        Assert.assertEquals(TSDBConstants.BOOLEAN_PRECISION, parameterMetaData_insert.getPrecision(8));
+        Assert.assertEquals("hello".getBytes().length, parameterMetaData_insert.getPrecision(9));
+        Assert.assertEquals("涛思数据".length(), parameterMetaData_insert.getPrecision(10));
     }
 
     @Test
@@ -71,8 +72,8 @@ public class RestfulParameterMetaDataTest {
         Assert.assertEquals(0, parameterMetaData_insert.getScale(1));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(2));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(3));
-        Assert.assertEquals(0, parameterMetaData_insert.getScale(4));
-        Assert.assertEquals(0, parameterMetaData_insert.getScale(5));
+        Assert.assertEquals(31, parameterMetaData_insert.getScale(4));
+        Assert.assertEquals(31, parameterMetaData_insert.getScale(5));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(6));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(7));
         Assert.assertEquals(0, parameterMetaData_insert.getScale(8));
@@ -164,7 +165,7 @@ public class RestfulParameterMetaDataTest {
             pstmt_insert.setObject(7, Byte.MAX_VALUE);
             pstmt_insert.setObject(8, true);
             pstmt_insert.setObject(9, "hello".getBytes());
-            pstmt_insert.setObject(10, "Hello");
+            pstmt_insert.setObject(10, "涛思数据");
             parameterMetaData_insert = pstmt_insert.getParameterMetaData();
 
             pstmt_select = conn.prepareStatement(sql_select);

src/connector/python/taos/cinterface.py

@@ -242,7 +242,7 @@ def _load_taos_linux():
 
 
 def _load_taos_darwin():
-    return ctypes.cDLL('libtaos.dylib')
+    return ctypes.CDLL('libtaos.dylib')
 
 
 def _load_taos_windows():

src/cq/src/cqMain.c

@@ -38,21 +38,6 @@
 #define cDebug(...) { if (cqDebugFlag & DEBUG_DEBUG) { taosPrintLog("CQ  ", cqDebugFlag, __VA_ARGS__); }}
 #define cTrace(...) { if (cqDebugFlag & DEBUG_TRACE) { taosPrintLog("CQ  ", cqDebugFlag, __VA_ARGS__); }}
 
-typedef struct {
-  int32_t  vgId;
-  int32_t  master;
-  int32_t  num;      // number of continuous streams
-  char     user[TSDB_USER_LEN];
-  char     pass[TSDB_KEY_LEN];
-  char     db[TSDB_DB_NAME_LEN];
-  FCqWrite cqWrite;
-  struct SCqObj *pHead;
-  void    *dbConn;
-  void    *tmrCtrl;
-  pthread_mutex_t mutex;
-  int32_t delete;
-  int32_t cqObjNum;
-} SCqContext;
 
 typedef struct SCqObj {
   tmr_h          tmrId;
@@ -439,7 +424,7 @@ static void cqProcessCreateTimer(void *param, void *tmrId) {
 
 // inner implement in tscStream.c
 TAOS_STREAM *taos_open_stream_withname(TAOS *taos, const char* desName, const char *sqlstr, void (*fp)(void *param, TAOS_RES *, TAOS_ROW row),
-                              int64_t stime, void *param, void (*callback)(void *));
+                              int64_t stime, void *param, void (*callback)(void *), void* cqhandle);
 
 static void cqCreateStream(SCqContext *pContext, SCqObj *pObj) {
   pObj->pContext = pContext;
@@ -453,7 +438,8 @@ static void cqCreateStream(SCqContext *pContext, SCqObj *pObj) {
   pObj->tmrId = 0;
 
   if (pObj->pStream == NULL) {
-    pObj->pStream = taos_open_stream_withname(pContext->dbConn, pObj->dstTable, pObj->sqlStr, cqProcessStreamRes, INT64_MIN, (void *)pObj->rid, NULL);
+    pObj->pStream = taos_open_stream_withname(pContext->dbConn, pObj->dstTable, pObj->sqlStr, cqProcessStreamRes, \
+                                               INT64_MIN, (void *)pObj->rid, NULL, pContext);
 
     // TODO the pObj->pStream may be released if error happens
     if (pObj->pStream) {

src/inc/tcq.h

@@ -31,6 +31,23 @@ typedef struct {
   FCqWrite cqWrite;
 } SCqCfg;
 
+// SCqContext
+typedef struct {
+  int32_t  vgId;
+  int32_t  master;
+  int32_t  num;      // number of continuous streams
+  char     user[TSDB_USER_LEN];
+  char     pass[TSDB_KEY_LEN];
+  char     db[TSDB_DB_NAME_LEN];
+  FCqWrite cqWrite;
+  struct SCqObj *pHead;
+  void    *dbConn;
+  void    *tmrCtrl;
+  pthread_mutex_t mutex;
+  int32_t delete;
+  int32_t cqObjNum;
+} SCqContext;
+
 // the following API shall be called by vnode
 void *cqOpen(void *ahandle, const SCqCfg *pCfg);
 void  cqClose(void *handle);

src/kit/taosdemo/taosdemo.c

@@ -625,6 +625,10 @@ static int64_t         g_totalChildTables = 0;
 static SQueryMetaInfo  g_queryInfo;
 static FILE *          g_fpOfInsertResult = NULL;
 
+#if _MSC_VER <= 1900
+#define __func__ __FUNCTION__
+#endif
+
 #define debugPrint(fmt, ...) \
     do { if (g_args.debug_print || g_args.verbose_print) \
       fprintf(stderr, "DEBG: "fmt, __VA_ARGS__); } while(0)

src/os/src/detail/osTime.c

@@ -43,7 +43,7 @@
  */
 int64_t user_mktime64(const unsigned int year0, const unsigned int mon0,
 		const unsigned int day, const unsigned int hour,
-		const unsigned int min, const unsigned int sec, int64_t timezone)
+		const unsigned int min, const unsigned int sec, int64_t time_zone)
 {
   unsigned int mon = mon0, year = year0;
 
@@ -61,7 +61,7 @@ int64_t user_mktime64(const unsigned int year0, const unsigned int mon0,
   res  = res*24;
   res  = ((res + hour) * 60 + min) * 60 + sec;
 
-  return (res + timezone);
+  return (res + time_zone);
 }
 
 // ==== mktime() kernel code =================//

src/util/inc/tutil.h

@@ -26,6 +26,7 @@ extern "C" {
 #include "taosdef.h"
 
 int32_t strdequote(char *src);
+int32_t strRmquote(char *z, int32_t len);
 size_t  strtrim(char *src);
 char *  strnchr(char *haystack, char needle, int32_t len, bool skipquote);
 char ** strsplit(char *src, const char *delim, int32_t *num);

src/util/src/tutil.c

@@ -52,6 +52,36 @@ int32_t strdequote(char *z) {
   return j + 1;  // only one quote, do nothing
 }
 
+
+int32_t strRmquote(char *z, int32_t len){  
+    // delete escape character: \\, \', \"
+    char delim = z[0];
+    if (delim != '\'' && delim != '\"') {
+      return len;
+    }
+  
+    int32_t cnt = 0;
+    int32_t j = 0;
+    for (uint32_t k = 1; k < len - 1; ++k) {
+      if (z[k] == '\\' || (z[k] == delim && z[k + 1] == delim)) {
+          z[j] = z[k + 1];
+  
+        cnt++;
+        j++;
+        k++;
+        continue;
+      }
+  
+      z[j] = z[k];
+      j++;
+    }
+  
+    z[j] = 0;
+    
+    return len - 2 - cnt;
+}
+
+
 size_t strtrim(char *z) {
   int32_t i = 0;
   int32_t j = 0;

tests/mas/Jenkinsfile

@@ -21,7 +21,7 @@ def pre_test(){
     cmake .. > /dev/null
     make > /dev/null
     make install > /dev/null
-    pip3 install ${WKC}/src/connector/python/linux/python3/
+    pip3 install ${WKC}/src/connector/python/ || echo 0
     '''
     return 1
 }

tests/pytest/cluster/clusterSetup.py

@@ -23,7 +23,8 @@ class Node:
         self.hostIP = hostIP
         self.hostName = hostName
         self.homeDir = homeDir
-        self.conn = Connection("{}@{}".format(username, hostName), connect_kwargs={"password": "{}".format(password)}) 
+        self.corePath = '/coredump'
+        self.conn = Connection("{}@{}".format(username, hostName), connect_kwargs={"password": "{}".format(password)})        
     
     def buildTaosd(self):
         try:
@@ -126,21 +127,37 @@ class Node:
         except Exception as e:
             print("remove taosd error for node %d " % self.index)
             logging.exception(e)
+    
+
+    def detectCoredumpFile(self):
+        try:
+            result = self.conn.run("find /coredump -name 'core_*' ", hide=True)
+            output = result.stdout
+            print("output: %s" % output)
+            return output
+        except Exception as e:
+            print("find coredump file error on node %d " % self.index)
+            logging.exception(e)
+        
 
 class Nodes:
     def __init__(self):
         self.tdnodes = []
-        self.tdnodes.append(Node(0, 'root', '52.143.103.7', 'node1', 'a', '/root/'))
-        self.tdnodes.append(Node(1, 'root', '52.250.48.222', 'node2', 'a', '/root/'))
-        self.tdnodes.append(Node(2, 'root', '51.141.167.23', 'node3', 'a', '/root/'))
-        self.tdnodes.append(Node(3, 'root', '52.247.207.173', 'node4', 'a', '/root/'))
-        self.tdnodes.append(Node(4, 'root', '51.141.166.100', 'node5', 'a', '/root/'))
+        self.tdnodes.append(Node(0, 'root', '192.168.17.194', 'taosdata', 'r', '/root/'))
+        # self.tdnodes.append(Node(1, 'root', '52.250.48.222', 'node2', 'a', '/root/'))
+        # self.tdnodes.append(Node(2, 'root', '51.141.167.23', 'node3', 'a', '/root/'))
+        # self.tdnodes.append(Node(3, 'root', '52.247.207.173', 'node4', 'a', '/root/'))
+        # self.tdnodes.append(Node(4, 'root', '51.141.166.100', 'node5', 'a', '/root/'))
 
     def stopOneNode(self, index):
+        self.tdnodes[index].stopTaosd()
         self.tdnodes[index].forceStopOneTaosd()
     
     def startOneNode(self, index):
         self.tdnodes[index].startOneTaosd()
+    
+    def detectCoredumpFile(self, index):
+        return self.tdnodes[index].detectCoredumpFile()
 
     def stopAllTaosd(self):
         for i in range(len(self.tdnodes)):
@@ -166,14 +183,32 @@ class Nodes:
         for i in range(len(self.tdnodes)):
             self.tdnodes[i].removeData()
 
-# kill taosd randomly every 10 mins
-nodes = Nodes()
-loop = 0
-while True:
-    loop = loop + 1    
-    index = random.randint(0, 4)
-    print("loop: %d, kill taosd on node%d" %(loop, index))
-    nodes.stopOneNode(index)
-    time.sleep(60)
-    nodes.startOneNode(index)
-    time.sleep(600)
\ No newline at end of file
+class Test:
+    def __init__(self):
+        self.nodes = Nodes()
+
+    # kill taosd randomly every 10 mins
+    def randomlyKillDnode(self):        
+        loop = 0
+        while True:                
+            index = random.randint(0, 4)
+            print("loop: %d, kill taosd on node%d" %(loop, index))
+            self.nodes.stopOneNode(index)
+            time.sleep(60)
+            self.nodes.startOneNode(index)
+            time.sleep(600)
+            loop = loop + 1
+    
+    def detectCoredump(self):
+        loop = 0
+        while True:
+            for i in range(len(self.nodes.tdnodes)):
+                result = self.nodes.detectCoredumpFile(i)
+                print("core file path is %s" % result)
+                if result and not result.isspace():
+                    self.nodes.stopAllTaosd()                    
+            print("sleep for 10 mins")
+            time.sleep(600)
+
+test = Test()
+test.detectCoredump()
\ No newline at end of file

tests/pytest/functions/showOfflineThresholdIs864000.py

@@ -25,7 +25,7 @@ class TDTestCase:
 
     def run(self):
         tdSql.query("show variables")
-        tdSql.checkData(51, 1, 864000)
+        tdSql.checkData(53, 1, 864000)
 
     def stop(self):
         tdSql.close()
@@ -33,4 +33,4 @@ class TDTestCase:
 
 
 tdCases.addWindows(__file__, TDTestCase())
-tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file
+tdCases.addLinux(__file__, TDTestCase())