fix:add interface for taos_get_current_db

include/client/taos.h

@@ -208,7 +208,7 @@ DLL_EXPORT TAOS_ROW *taos_result_block(TAOS_RES *res);
 
 DLL_EXPORT const char *taos_get_server_info(TAOS *taos);
 DLL_EXPORT const char *taos_get_client_info();
-DLL_EXPORT const char *taos_get_current_db(TAOS *taos, size_t *required);
+DLL_EXPORT int         taos_get_current_db(TAOS *taos, char *database, int len, int *required);
 
 DLL_EXPORT const char *taos_errstr(TAOS_RES *res);
 DLL_EXPORT int         taos_errno(TAOS_RES *res);

source/client/src/clientMain.c

@@ -686,13 +686,32 @@ const char *taos_get_server_info(TAOS *taos) {
   return pTscObj->sDetailVer;
 }
 
-const char *taos_get_current_db(TAOS *taos, size_t *required) {
+int taos_get_current_db(TAOS *taos, char *database, int len, int *required) {
   STscObj *pTscObj = acquireTscObj(*(int64_t *)taos);
   if (pTscObj == NULL) {
     terrno = TSDB_CODE_TSC_DISCONNECTED;
-    return NULL;
+    return -1;
+  }
+
+  int code = TSDB_CODE_SUCCESS;
+  taosThreadMutexLock(&pTscObj->mutex);
+  if(database == NULL || len <= 0){
+    if(required != NULL) *required = strlen(pTscObj->db) + 1;
+    terrno = TSDB_CODE_INVALID_PARA;
+    return -1;
   }
-  return pTscObj->db;
+
+  if(len < strlen(pTscObj->db) + 1){
+    tstrncpy(database, pTscObj->db, len);
+    if(required) *required = strlen(pTscObj->db) + 1;
+    terrno = TSDB_CODE_INVALID_PARA;
+    code = -1;
+  }else{
+    strcpy(database, pTscObj->db);
+    code = 0;
+  }
+  taosThreadMutexUnlock(&pTscObj->mutex);
+  return code;
 }
 
 static void destoryTablesReq(void *p) {

source/common/src/systable.c

@@ -179,7 +179,6 @@ static const SSysDbTableSchema userTagsSchema[] = {
 static const SSysDbTableSchema userColsSchema[] = {
     {.name = "table_name", .bytes = SYSTABLE_SCH_TABLE_NAME_LEN, .type = TSDB_DATA_TYPE_VARCHAR, .sysInfo = false},
     {.name = "db_name", .bytes = SYSTABLE_SCH_DB_NAME_LEN, .type = TSDB_DATA_TYPE_VARCHAR, .sysInfo = false},
-    {.name = "stable_name", .bytes = SYSTABLE_SCH_TABLE_NAME_LEN, .type = TSDB_DATA_TYPE_VARCHAR, .sysInfo = false},
     {.name = "col_name", .bytes = TSDB_COL_NAME_LEN - 1 + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR, .sysInfo = false},
     {.name = "col_type", .bytes = 32 + VARSTR_HEADER_SIZE, .type = TSDB_DATA_TYPE_VARCHAR, .sysInfo = false},
     {.name = "col_length", .bytes = 4, .type = TSDB_DATA_TYPE_INT, .sysInfo = false},

source/libs/executor/src/sysscanoperator.c

@@ -140,6 +140,9 @@ static int32_t sysTableUserTagsFillOneTableTags(const SSysTableScanInfo* pInfo,
                                                 SMetaReader* smrChildTable, const char* dbname, const char* tableName,
                                                 int32_t* pNumOfRows, const SSDataBlock* dataBlock);
 
+static int32_t sysTableUserColsFillOneTableCols(const SSysTableScanInfo* pInfo, SMetaReader* smrTable, const char* dbname,
+                                                int32_t* pNumOfRows, const SSDataBlock* dataBlock);
+
 static void relocateAndFilterSysTagsScanResult(SSysTableScanInfo* pInfo, int32_t numOfRows, SSDataBlock* dataBlock,
                                                SFilterInfo* pFilterInfo);
 
@@ -443,38 +446,26 @@ static SSDataBlock* sysTableScanUserCols(SOperatorInfo* pOperator) {
     char tableName[TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
     STR_TO_VARSTR(tableName, condTableName);
 
-    SMetaReader smrChildTable = {0};
-    metaReaderInit(&smrChildTable, pInfo->readHandle.meta, 0);
-    int32_t code = metaGetTableEntryByName(&smrChildTable, condTableName);
+    SMetaReader smrTable = {0};
+    metaReaderInit(&smrTable, pInfo->readHandle.meta, 0);
+    int32_t code = metaGetTableEntryByName(&smrTable, condTableName);
     if (code != TSDB_CODE_SUCCESS) {
       // terrno has been set by metaGetTableEntryByName, therefore, return directly
-      metaReaderClear(&smrChildTable);
+      metaReaderClear(&smrTable);
       blockDataDestroy(dataBlock);
       pInfo->loadInfo.totalRows = 0;
       return NULL;
     }
 
-    if (smrChildTable.me.type != TSDB_CHILD_TABLE) {
-      metaReaderClear(&smrChildTable);
+    if (smrTable.me.type == TSDB_CHILD_TABLE) {
+      metaReaderClear(&smrTable);
       blockDataDestroy(dataBlock);
       pInfo->loadInfo.totalRows = 0;
       return NULL;
     }
 
-    SMetaReader smrSuperTable = {0};
-    metaReaderInit(&smrSuperTable, pInfo->readHandle.meta, META_READER_NOLOCK);
-    code = metaGetTableEntryByUid(&smrSuperTable, smrChildTable.me.ctbEntry.suid);
-    if (code != TSDB_CODE_SUCCESS) {
-      // terrno has been set by metaGetTableEntryByUid
-      metaReaderClear(&smrSuperTable);
-      metaReaderClear(&smrChildTable);
-      blockDataDestroy(dataBlock);
-      return NULL;
-    }
-
-    sysTableUserTagsFillOneTableTags(pInfo, &smrSuperTable, &smrChildTable, dbname, tableName, &numOfRows, dataBlock);
-    metaReaderClear(&smrSuperTable);
-    metaReaderClear(&smrChildTable);
+    sysTableUserColsFillOneTableCols(pInfo, &smrTable, dbname, &numOfRows, dataBlock);
+    metaReaderClear(&smrTable);
 
     if (numOfRows > 0) {
       relocateAndFilterSysTagsScanResult(pInfo, numOfRows, dataBlock, pOperator->exprSupp.pFilterInfo);
@@ -492,29 +483,11 @@ static SSDataBlock* sysTableScanUserCols(SOperatorInfo* pOperator) {
   }
 
   while ((ret = metaTbCursorNext(pInfo->pCur)) == 0) {
-    if (pInfo->pCur->mr.me.type != TSDB_CHILD_TABLE) {
+    if (pInfo->pCur->mr.me.type == TSDB_CHILD_TABLE) {
       continue;
     }
 
-    char tableName[TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
-    STR_TO_VARSTR(tableName, pInfo->pCur->mr.me.name);
-
-    SMetaReader smrSuperTable = {0};
-    metaReaderInit(&smrSuperTable, pInfo->readHandle.meta, 0);
-    uint64_t suid = pInfo->pCur->mr.me.ctbEntry.suid;
-    int32_t  code = metaGetTableEntryByUid(&smrSuperTable, suid);
-    if (code != TSDB_CODE_SUCCESS) {
-      qError("failed to get super table meta, uid:0x%" PRIx64 ", code:%s, %s", suid, tstrerror(terrno),
-             GET_TASKID(pTaskInfo));
-      metaReaderClear(&smrSuperTable);
-      metaCloseTbCursor(pInfo->pCur);
-      pInfo->pCur = NULL;
-      T_LONG_JMP(pTaskInfo->env, terrno);
-    }
-
-    sysTableUserTagsFillOneTableTags(pInfo, &smrSuperTable, &pInfo->pCur->mr, dbname, tableName, &numOfRows, dataBlock);
-
-    metaReaderClear(&smrSuperTable);
+    sysTableUserColsFillOneTableCols(pInfo, &pInfo->pCur->mr, dbname, &numOfRows, dataBlock);
 
     if (numOfRows >= pOperator->resultInfo.capacity) {
       relocateAndFilterSysTagsScanResult(pInfo, numOfRows, dataBlock, pOperator->exprSupp.pFilterInfo);
@@ -857,6 +830,72 @@ static int32_t sysTableUserTagsFillOneTableTags(const SSysTableScanInfo* pInfo,
   return TSDB_CODE_SUCCESS;
 }
 
+static int32_t sysTableUserColsFillOneTableCols(const SSysTableScanInfo* pInfo, SMetaReader* smrTable, const char* dbname,
+                                                int32_t* pNumOfRows, const SSDataBlock* dataBlock) {
+  char tableName[TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
+  STR_TO_VARSTR(tableName, smrTable->me.name);
+
+  SSchemaWrapper schemaRow = {0};
+  if(smrTable->me.type == TSDB_SUPER_TABLE){
+    schemaRow  = smrTable->me.stbEntry.schemaRow;
+  }else if(smrTable->me.type == TSDB_NORMAL_TABLE){
+    schemaRow  = smrTable->me.ntbEntry.schemaRow;
+  }
+  int32_t numOfRows = *pNumOfRows;
+
+  int32_t numOfCols = schemaRow.nCols;
+  for (int32_t i = 0; i < numOfCols; ++i) {
+    SColumnInfoData* pColInfoData = NULL;
+
+    // table name
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 0);
+    colDataAppend(pColInfoData, numOfRows, tableName, tableName == NULL ? true : false);
+
+    // database name
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 1);
+    colDataAppend(pColInfoData, numOfRows, dbname, false);
+
+    // col name
+    char colName[TSDB_COL_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
+    STR_TO_VARSTR(colName, schemaRow.pSchema[i].name);
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 2);
+    colDataAppend(pColInfoData, numOfRows, colName, false);
+
+    // col type
+    int8_t colType = schemaRow.pSchema[i].type;
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 3);
+    char colTypeStr[VARSTR_HEADER_SIZE + 32];
+    int  colTypeLen = sprintf(varDataVal(colTypeStr), "%s", tDataTypes[colType].name);
+    if (colType == TSDB_DATA_TYPE_VARCHAR) {
+      colTypeLen += sprintf(varDataVal(colTypeStr) + colTypeLen, "(%d)",
+                            (int32_t)(schemaRow.pSchema[i].bytes - VARSTR_HEADER_SIZE));
+    } else if (colType == TSDB_DATA_TYPE_NCHAR) {
+      colTypeLen += sprintf(
+          varDataVal(colTypeStr) + colTypeLen, "(%d)",
+          (int32_t)((schemaRow.pSchema[i].bytes - VARSTR_HEADER_SIZE) / TSDB_NCHAR_SIZE));
+    }
+    varDataSetLen(colTypeStr, colTypeLen);
+    colDataAppend(pColInfoData, numOfRows, (char*)colTypeStr, false);
+
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 4);
+    colDataAppend(pColInfoData, numOfRows, (const char*)&schemaRow.pSchema[i].bytes, false);
+
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 5);
+    colDataAppend(pColInfoData, numOfRows, NULL, true);
+
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 6);
+    colDataAppend(pColInfoData, numOfRows, NULL, true);
+
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 7);
+    colDataAppend(pColInfoData, numOfRows, NULL, true);
+    ++numOfRows;
+  }
+
+  *pNumOfRows = numOfRows;
+
+  return TSDB_CODE_SUCCESS;
+}
+
 static SSDataBlock* buildInfoSchemaTableMetaBlock(char* tableName) {
   size_t               size = 0;
   const SSysTableMeta* pMeta = NULL;

source/libs/parser/src/parAstParser.c

@@ -147,16 +147,6 @@ static int32_t collectMetaKeyFromInsTags(SCollectMetaKeyCxt* pCxt) {
   return code;
 }
 
-static int32_t collectMetaKeyFromInsCols(SCollectMetaKeyCxt* pCxt) {
-  SSelectStmt* pSelect = (SSelectStmt*)pCxt->pStmt;
-  SName        name = {0};
-  int32_t      code = getVnodeSysTableTargetName(pCxt->pParseCxt->acctId, pSelect->pWhere, &name);
-  if (TSDB_CODE_SUCCESS == code) {
-    code = collectMetaKeyFromInsTagsImpl(pCxt, &name);
-  }
-  return code;
-}
-
 static int32_t collectMetaKeyFromRealTableImpl(SCollectMetaKeyCxt* pCxt, const char* pDb, const char* pTable,
                                                AUTH_TYPE authType) {
   int32_t code = reserveTableMetaInCache(pCxt->pParseCxt->acctId, pDb, pTable, pCxt->pMetaCache);
@@ -180,11 +170,6 @@ static int32_t collectMetaKeyFromRealTableImpl(SCollectMetaKeyCxt* pCxt, const c
       QUERY_NODE_SELECT_STMT == nodeType(pCxt->pStmt)) {
     code = collectMetaKeyFromInsTags(pCxt);
   }
-  if (TSDB_CODE_SUCCESS == code &&
-      0 == strcmp(pTable, TSDB_INS_TABLE_COLS) &&
-      QUERY_NODE_SELECT_STMT == nodeType(pCxt->pStmt)) {
-    code = collectMetaKeyFromInsCols(pCxt);
-  }
   return code;
 }
 
@@ -490,19 +475,6 @@ static int32_t collectMetaKeyFromShowTags(SCollectMetaKeyCxt* pCxt, SShowStmt* p
   return code;
 }
 
-static int32_t collectMetaKeyFromShowCols(SCollectMetaKeyCxt* pCxt, SShowStmt* pStmt) {
-  int32_t code = reserveTableMetaInCache(pCxt->pParseCxt->acctId, TSDB_INFORMATION_SCHEMA_DB, TSDB_INS_TABLE_COLS,
-                                         pCxt->pMetaCache);
-  if (TSDB_CODE_SUCCESS == code) {
-    code = reserveDbVgInfoInCache(pCxt->pParseCxt->acctId, ((SValueNode*)pStmt->pDbName)->literal, pCxt->pMetaCache);
-  }
-  if (TSDB_CODE_SUCCESS == code && NULL != pStmt->pTbName) {
-    code = reserveTableVgroupInCache(pCxt->pParseCxt->acctId, ((SValueNode*)pStmt->pDbName)->literal,
-                                     ((SValueNode*)pStmt->pTbName)->literal, pCxt->pMetaCache);
-  }
-  return code;
-}
-
 static int32_t collectMetaKeyFromShowStableTags(SCollectMetaKeyCxt* pCxt, SShowTableTagsStmt* pStmt) {
   return collectMetaKeyFromRealTableImpl(pCxt, ((SValueNode*)pStmt->pDbName)->literal,
                                          ((SValueNode*)pStmt->pTbName)->literal, AUTH_TYPE_READ);

source/libs/parser/src/parTranslater.c

@@ -162,13 +162,6 @@ static const SSysTableShowAdapter sysTableShowAdapter[] = {
     .numOfShowCols = 1,
     .pShowCols = {"*"}
   },
-  {
-    .showType = QUERY_NODE_SHOW_TAGS_STMT,
-    .pDbName = TSDB_INFORMATION_SCHEMA_DB,
-    .pTableName = TSDB_INS_TABLE_COLS,
-    .numOfShowCols = 1,
-    .pShowCols = {"*"}
-  },
   {
     .showType = QUERY_NODE_SHOW_USERS_STMT,
     .pDbName = TSDB_INFORMATION_SCHEMA_DB,