[td-1151] add test cases and fix the found bugs.

src/client/inc/tscUtil.h

@@ -198,7 +198,7 @@ int32_t tscValidateName(SSQLToken* pToken);
 
 void tscIncStreamExecutionCount(void* pStream);
 
-bool tscValidateColumnId(STableMetaInfo* pTableMetaInfo, int32_t colId);
+bool tscValidateColumnId(STableMetaInfo* pTableMetaInfo, int32_t colId, int32_t numOfParams);
 
 // get starter position of metric query condition (query on tags) in SSqlCmd.payload
 SCond* tsGetSTableQueryCond(STagCond* pCond, uint64_t uid);

src/client/inc/tsclient.h

@@ -195,9 +195,9 @@ typedef struct STableDataBlocks {
 
 typedef struct SQueryInfo {
   int16_t          command;       // the command may be different for each subclause, so keep it seperately.
-  uint32_t         type;          // query/insert/import type
+  uint32_t         type;          // query/insert type
   char             slidingTimeUnit;
-  STimeWindow      window;
+  STimeWindow      window;        // query time window
   int64_t          intervalTime;  // aggregation time interval
   int64_t          slidingTime;   // sliding window in mseconds
   SSqlGroupbyExpr  groupbyExpr;   // group by tags info
@@ -216,6 +216,7 @@ typedef struct SQueryInfo {
   char *           msg;           // pointer to the pCmd->payload to keep error message temporarily
   int64_t          clauseLimit;   // limit for current sub clause
   int64_t          prjOffset;     // offset value in the original sql expression, only applied at client side
+  int32_t          udColumnId;    // current user-defined constant output field column id, monotonically decreases from TSDB_UD_COLUMN_INDEX
 } SQueryInfo;
 
 typedef struct {

src/client/src/tscFunctionImpl.c

@@ -2902,12 +2902,12 @@ static FORCE_INLINE void date_col_output_function_f(SQLFunctionCtx *pCtx, int32_
 }
 
 static void col_project_function(SQLFunctionCtx *pCtx) {
-  if (pCtx->numOfParams == 1) {  // the number of output rows should not affect the final number of rows, so set it to be 1
-    INC_INIT_VAL(pCtx, 1);
+  if (pCtx->numOfParams == 2) {  // the number of output rows should not affect the final number of rows, so set it to be 0
+    SET_VAL(pCtx, pCtx->size, 1);
 
     char* output = pCtx->aOutputBuf;
     for(int32_t i = 0; i < pCtx->size; ++i) {
-      tVariantDump(&pCtx->param[0], output, pCtx->outputType, true);
+      tVariantDump(&pCtx->param[1], output, pCtx->outputType, true);
       output += pCtx->outputBytes;
     }
 
@@ -2936,11 +2936,16 @@ static void col_project_function_f(SQLFunctionCtx *pCtx, int32_t index) {
   if (pCtx->param[0].i64Key == 1 && pResInfo->numOfRes >= 1) {
     return;
   }
-  
-  INC_INIT_VAL(pCtx, 1);
-  char *pData = GET_INPUT_CHAR_INDEX(pCtx, index);
-  memcpy(pCtx->aOutputBuf, pData, pCtx->inputBytes);
-  
+
+  if (pCtx->numOfParams == 2) {  // the number of output rows should not affect the final number of rows, so set it to be 0
+    SET_VAL(pCtx, pCtx->size, 1);
+    tVariantDump(&pCtx->param[1], pCtx->aOutputBuf, pCtx->outputType, true);
+  } else {
+    INC_INIT_VAL(pCtx, 1);
+    char *pData = GET_INPUT_CHAR_INDEX(pCtx, index);
+    memcpy(pCtx->aOutputBuf, pData, pCtx->inputBytes);
+  }
+
   pCtx->aOutputBuf += pCtx->inputBytes;
 }
 

src/client/src/tscSQLParser.c

@@ -1094,18 +1094,6 @@ int32_t setObjFullName(char* fullName, const char* account, SSQLToken* pDB, SSQL
   return (totalLen < TSDB_TABLE_FNAME_LEN) ? TSDB_CODE_SUCCESS : TSDB_CODE_TSC_INVALID_SQL;
 }
 
-static void extractColumnNameFromString(tSQLExprItem* pItem) {
-  if (pItem->pNode->nSQLOptr == TK_STRING) {
-    pItem->pNode->val.nLen = strdequote(pItem->pNode->val.pz);
-    pItem->pNode->nSQLOptr = TK_ID;
-
-    SSQLToken* pIdToken = &pItem->pNode->colInfo;
-    pIdToken->type = TK_ID;
-    pIdToken->z = pItem->pNode->val.pz;
-    pIdToken->n = pItem->pNode->val.nLen;
-  }
-}
-
 static int32_t handleArithmeticExpr(SSqlCmd* pCmd, int32_t clauseIndex, int32_t exprIndex, tSQLExprItem* pItem) {
   const char* msg1 = "invalid column name, or illegal column type";
   const char* msg2 = "invalid arithmetic expression in select clause";
@@ -1234,6 +1222,11 @@ static int32_t handleArithmeticExpr(SSqlCmd* pCmd, int32_t clauseIndex, int32_t
   return TSDB_CODE_SUCCESS;
 }
 
+static void tscInsertPrimaryTSSourceColumn(SQueryInfo* pQueryInfo, SColumnIndex* pIndex) {
+  SColumnIndex tsCol = {.tableIndex = pIndex->tableIndex, .columnIndex = PRIMARYKEY_TIMESTAMP_COL_INDEX};
+  tscColumnListInsert(pQueryInfo->colList, &tsCol);
+}
+
 int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSelection, bool isSTable) {
   assert(pSelection != NULL && pCmd != NULL);
 
@@ -1254,15 +1247,12 @@ int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSel
     // project on all fields
     int32_t optr = pItem->pNode->nSQLOptr;
 
-    if (optr == TK_ALL || optr == TK_ID || optr == TK_STRING || (optr == TK_INTEGER || optr == TK_FLOAT)) {
+    if (optr == TK_ALL || optr == TK_ID || optr == TK_STRING || optr == TK_INTEGER || optr == TK_FLOAT) {
       // it is actually a function, but the function name is invalid
       if (pItem->pNode->nSQLOptr == TK_ID && (pItem->pNode->colInfo.z == NULL && pItem->pNode->colInfo.n == 0)) {
         return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg5);
       }
 
-      // if the name of column is quoted, remove it and set the right information for later process
-      extractColumnNameFromString(pItem);
-
       // select table_name1.field_name1, table_name2.field_name2  from table_name1, table_name2
       if (addProjectionExprAndResultField(pCmd, pQueryInfo, pItem) != TSDB_CODE_SUCCESS) {
         return TSDB_CODE_TSC_INVALID_SQL;
@@ -1292,6 +1282,13 @@ int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSel
     }
   }
 
+  // there is only one user-defined column in the final result field, add the timestamp column.
+  size_t numOfSrcCols = taosArrayGetSize(pQueryInfo->colList);
+  if (numOfSrcCols <= 0 && !tscQueryTags(pQueryInfo)) {
+    SColumnIndex index = {0};
+    tscInsertPrimaryTSSourceColumn(pQueryInfo, &index);
+  }
+
   if (!functionCompatibleCheck(pQueryInfo)) {
     return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg2);
   }
@@ -1431,17 +1428,11 @@ static int32_t doAddProjectionExprAndResultFields(SQueryInfo* pQueryInfo, SColum
   return numOfTotalColumns;
 }
 
-static void tscInsertPrimaryTSSourceColumn(SQueryInfo* pQueryInfo, SColumnIndex* pIndex) {
-  SColumnIndex tsCol = {.tableIndex = pIndex->tableIndex, .columnIndex = PRIMARYKEY_TIMESTAMP_COL_INDEX};
-  tscColumnListInsert(pQueryInfo->colList, &tsCol);
-}
-
 int32_t addProjectionExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, tSQLExprItem* pItem) {
   const char* msg0 = "invalid column name";
   const char* msg1 = "tag for normal table query is not allowed";
-  
-  int32_t startPos = (int32_t)tscSqlExprNumOfExprs(pQueryInfo);
 
+  int32_t startPos = (int32_t)tscSqlExprNumOfExprs(pQueryInfo);
   int32_t optr = pItem->pNode->nSQLOptr;
 
   if (optr == TK_ALL) {  // project on all fields
@@ -1465,40 +1456,43 @@ int32_t addProjectionExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, t
 
     // add the primary timestamp column even though it is not required by user
     tscInsertPrimaryTSSourceColumn(pQueryInfo, &index);
-  } else if (optr == TK_ID || optr == TK_INTEGER || optr == TK_FLOAT) {  // simple column projection query
+  } else if (optr == TK_STRING || optr == TK_INTEGER || optr == TK_FLOAT) {  // simple column projection query
     SColumnIndex index = COLUMN_INDEX_INITIALIZER;
 
     // user-specified constant value as a new result column
-    if ((optr == TK_INTEGER || optr == TK_FLOAT) || (getColumnIndexByName(pCmd, &pItem->pNode->colInfo, pQueryInfo, &index) != TSDB_CODE_SUCCESS)) {
-      index.columnIndex = TSDB_UD_COLUMN_INDEX;
-      index.tableIndex = 0;
+    index.columnIndex = (pQueryInfo->udColumnId--);
+    index.tableIndex = 0;
 
-      SSchema colSchema = tGetUserSpecifiedColumnSchema(pItem->pNode->val.pz, pItem->pNode->val.nType, pItem->aliasName);
-      SSqlExpr* pExpr = tscAddSpecialColumnForSelect(pQueryInfo, startPos, TSDB_FUNC_PRJ, &index, &colSchema, TSDB_COL_UDC);
-      pExpr->numOfParams = 1;
-      tVariantAssign(&pExpr->param[0], &pItem->pNode->val);
+    SSchema colSchema = tGetUserSpecifiedColumnSchema(&pItem->pNode->val, pItem->aliasName);
+    SSqlExpr* pExpr =
+        tscAddSpecialColumnForSelect(pQueryInfo, startPos, TSDB_FUNC_PRJ, &index, &colSchema, TSDB_COL_UDC);
 
-    } else { // columns from the queried table
-      TSDB_QUERY_SET_TYPE(pQueryInfo->type, TSDB_QUERY_TYPE_PROJECTION_QUERY);
+    // NOTE: the first parameter is reserved for the tag column id during join query process.
+    pExpr->numOfParams = 2;
+    tVariantAssign(&pExpr->param[1], &pItem->pNode->val);
+  } else if (optr == TK_ID) {
+    SColumnIndex index = COLUMN_INDEX_INITIALIZER;
 
-      if (index.columnIndex == TSDB_TBNAME_COLUMN_INDEX) {
-        SSchema colSchema = tGetTableNameColumnSchema();
-        tscAddSpecialColumnForSelect(pQueryInfo, startPos, TSDB_FUNC_TAGPRJ, &index, &colSchema, TSDB_COL_TAG);
-      } else {
-        STableMetaInfo* pTableMetaInfo = tscGetMetaInfo(pQueryInfo, index.tableIndex);
-        STableMeta*     pTableMeta = pTableMetaInfo->pTableMeta;
+    if (getColumnIndexByName(pCmd, &pItem->pNode->colInfo, pQueryInfo, &index) != TSDB_CODE_SUCCESS) {
+      return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg0);
+    }
 
-        if (index.columnIndex >= tscGetNumOfColumns(pTableMeta) && UTIL_TABLE_IS_NORMAL_TABLE(pTableMetaInfo)) {
-          return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg1);
-        }
+    if (index.columnIndex == TSDB_TBNAME_COLUMN_INDEX) {
+      SSchema colSchema = tGetTableNameColumnSchema();
+      tscAddSpecialColumnForSelect(pQueryInfo, startPos, TSDB_FUNC_TAGPRJ, &index, &colSchema, TSDB_COL_TAG);
+    } else {
+      STableMetaInfo* pTableMetaInfo = tscGetMetaInfo(pQueryInfo, index.tableIndex);
+      STableMeta*     pTableMeta = pTableMetaInfo->pTableMeta;
 
-        addProjectQueryCol(pQueryInfo, startPos, &index, pItem);
+      if (index.columnIndex >= tscGetNumOfColumns(pTableMeta) && UTIL_TABLE_IS_NORMAL_TABLE(pTableMetaInfo)) {
+        return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg1);
       }
 
-      // add the primary timestamp column even though it is not required by user
-      tscInsertPrimaryTSSourceColumn(pQueryInfo, &index);
+      addProjectQueryCol(pQueryInfo, startPos, &index, pItem);
     }
 
+    // add the primary timestamp column even though it is not required by user
+    tscInsertPrimaryTSSourceColumn(pQueryInfo, &index);
   } else {
     return TSDB_CODE_TSC_INVALID_SQL;
   }
@@ -2069,7 +2063,7 @@ int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int32_t col
 
 // todo refactor
 static SColumnList getColumnList(int32_t num, int16_t tableIndex, int32_t columnIndex) {
-  assert(num == 1 && columnIndex >= -2 && tableIndex >= 0);
+  assert(num == 1 && tableIndex >= 0);
 
   SColumnList columnList = {0};
   columnList.num = num;
@@ -4706,7 +4700,7 @@ int32_t validateFunctionsInIntervalOrGroupbyQuery(SSqlCmd* pCmd, SQueryInfo* pQu
       }
     }
 
-    if (pExpr->functionId == TSDB_FUNC_PRJ || pExpr->functionId == TSDB_FUNC_DIFF ||
+    if ((pExpr->functionId == TSDB_FUNC_PRJ && pExpr->numOfParams == 0) || pExpr->functionId == TSDB_FUNC_DIFF ||
         pExpr->functionId == TSDB_FUNC_ARITHM) {
       isProjectionFunction = true;
     }

src/client/src/tscServer.c

@@ -628,9 +628,12 @@ int tscBuildQueryMsg(SSqlObj *pSql, SSqlInfo *pInfo) {
   SQueryInfo *pQueryInfo = tscGetQueryInfoDetail(pCmd, pCmd->clauseIndex);
   STableMetaInfo *pTableMetaInfo = tscGetMetaInfo(pQueryInfo, 0);
   STableMeta * pTableMeta = pTableMetaInfo->pTableMeta;
-  
-  if (taosArrayGetSize(pQueryInfo->colList) <= 0 && !tscQueryTags(pQueryInfo)) {
-    tscError("%p illegal value of numOfCols in query msg: %d", pSql, tscGetNumOfColumns(pTableMeta));
+
+  size_t numOfSrcCols = taosArrayGetSize(pQueryInfo->colList);
+  if (numOfSrcCols <= 0 && !tscQueryTags(pQueryInfo)) {
+    tscError("%p illegal value of numOfCols in query msg: %"PRIu64", table cols:%d", pSql, numOfSrcCols,
+        tscGetNumOfColumns(pTableMeta));
+
     return TSDB_CODE_TSC_INVALID_SQL;
   }
   
@@ -728,7 +731,7 @@ int tscBuildQueryMsg(SSqlObj *pSql, SSqlInfo *pInfo) {
   for (int32_t i = 0; i < tscSqlExprNumOfExprs(pQueryInfo); ++i) {
     SSqlExpr *pExpr = tscSqlExprGet(pQueryInfo, i);
 
-    if (!tscValidateColumnId(pTableMetaInfo, pExpr->colInfo.colId)) {
+    if (!tscValidateColumnId(pTableMetaInfo, pExpr->colInfo.colId, pExpr->numOfParams)) {
       /* column id is not valid according to the cached table meta, the table meta is expired */
       tscError("%p table schema is not matched with parsed sql", pSql);
       return TSDB_CODE_TSC_INVALID_SQL;

src/client/src/tscSubquery.c

@@ -353,11 +353,12 @@ static int32_t tscLaunchRealSubqueries(SSqlObj* pSql) {
       pExpr = tscSqlExprGet(pQueryInfo, 0);
     }
 
-    // set the join condition tag column info, to do extract method
+    // set the join condition tag column info, todo extract method
     if (UTIL_TABLE_IS_SUPER_TABLE(pTableMetaInfo)) {
       assert(pQueryInfo->tagCond.joinInfo.hasJoin);
       int16_t colId = tscGetJoinTagColIdByUid(&pQueryInfo->tagCond, pTableMetaInfo->pTableMeta->id.uid);
 
+      // set the tag column id for executor to extract correct tag value
       pExpr->param[0].i64Key = colId;
       pExpr->numOfParams = 1;
     }

src/client/src/tscUtil.c

@@ -937,8 +937,8 @@ static SSqlExpr* doBuildSqlExpr(SQueryInfo* pQueryInfo, int16_t functionId, SCol
   // set the correct columnIndex index
   if (pColIndex->columnIndex == TSDB_TBNAME_COLUMN_INDEX) {
     pExpr->colInfo.colId = TSDB_TBNAME_COLUMN_INDEX;
-  } else if (pColIndex->columnIndex == TSDB_UD_COLUMN_INDEX) {
-    pExpr->colInfo.colId = TSDB_UD_COLUMN_INDEX;
+  } else if (pColIndex->columnIndex <= TSDB_UD_COLUMN_INDEX) {
+    pExpr->colInfo.colId = pColIndex->columnIndex;
   } else {
     if (TSDB_COL_IS_TAG(colType)) {
       SSchema* pSchema = tscGetTableTagSchema(pTableMetaInfo->pTableMeta);
@@ -1290,12 +1290,12 @@ void tscIncStreamExecutionCount(void* pStream) {
   ps->num += 1;
 }
 
-bool tscValidateColumnId(STableMetaInfo* pTableMetaInfo, int32_t colId) {
+bool tscValidateColumnId(STableMetaInfo* pTableMetaInfo, int32_t colId, int32_t numOfParams) {
   if (pTableMetaInfo->pTableMeta == NULL) {
     return false;
   }
 
-  if (colId == TSDB_TBNAME_COLUMN_INDEX || colId == TSDB_UD_COLUMN_INDEX) {
+  if (colId == TSDB_TBNAME_COLUMN_INDEX || (colId <= TSDB_UD_COLUMN_INDEX && numOfParams == 2)) {
     return true;
   }
 
@@ -1511,6 +1511,7 @@ void tscInitQueryInfo(SQueryInfo* pQueryInfo) {
   assert(pQueryInfo->exprList == NULL);
   pQueryInfo->exprList = taosArrayInit(4, POINTER_BYTES);
   pQueryInfo->colList  = taosArrayInit(4, POINTER_BYTES);
+  pQueryInfo->udColumnId = TSDB_UD_COLUMN_INDEX;
 }
 
 int32_t tscAddSubqueryInfo(SSqlCmd* pCmd) {

src/common/inc/tname.h

@@ -4,6 +4,7 @@
 #include "os.h"
 #include "taosmsg.h"
 #include "tstoken.h"
+#include "tvariant.h"
 
 typedef struct SDataStatis {
   int16_t colId;
@@ -28,7 +29,7 @@ void extractTableNameFromToken(SSQLToken *pToken, SSQLToken* pTable);
 
 SSchema tGetTableNameColumnSchema();
 
-SSchema tGetUserSpecifiedColumnSchema(const char* v, int16_t type, const char* name);
+SSchema tGetUserSpecifiedColumnSchema(tVariant* pVal, const char* name);
 
 bool tscValidateTableNameLength(size_t len);
 

src/common/src/tname.c

@@ -4,6 +4,7 @@
 #include "tname.h"
 #include "tstoken.h"
 #include "ttokendef.h"
+#include "tvariant.h"
 
 // todo refactor
 UNUSED_FUNC static FORCE_INLINE const char* skipSegments(const char* input, char delim, int32_t num) {
@@ -47,19 +48,23 @@ SSchema tGetTableNameColumnSchema() {
   return s;
 }
 
-SSchema tGetUserSpecifiedColumnSchema(const char* v, int16_t type, const char* name) {
+SSchema tGetUserSpecifiedColumnSchema(tVariant* pVal, const char* name) {
   SSchema s = {0};
 
-  s.type  = type;
+  s.type  = pVal->nType;
   if (s.type == TSDB_DATA_TYPE_BINARY || s.type == TSDB_DATA_TYPE_NCHAR) {
-    size_t len = strlen(v);
-    s.bytes = len + VARSTR_HEADER_SIZE;
+    s.bytes = pVal->nLen + VARSTR_HEADER_SIZE;
   } else {
-    s.bytes = tDataTypeDesc[type].nSize;
+    s.bytes = tDataTypeDesc[pVal->nType].nSize;
   }
 
   s.colId = TSDB_UD_COLUMN_INDEX;
-  tstrncpy(s.name, name, sizeof(s.name));
+  if (name != NULL) {
+    tstrncpy(s.name, name, sizeof(s.name));
+  } else {
+    tVariantToString(pVal, s.name);
+    strdequote(s.name);
+  }
 
   return s;
 }

src/inc/taosdef.h

@@ -287,7 +287,7 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size);
 #define TSDB_MAX_REPLICA          5
 
 #define TSDB_TBNAME_COLUMN_INDEX        (-1)
-#define TSDB_UD_COLUMN_INDEX           (-2)
+#define TSDB_UD_COLUMN_INDEX            (-100)
 #define TSDB_MULTI_METERMETA_MAX_NUM    100000  // maximum batch size allowed to load metermeta
 
 #define TSDB_MIN_CACHE_BLOCK_SIZE       1

src/inc/taosmsg.h

@@ -169,7 +169,7 @@ enum _mgmt_table {
 
 #define TSDB_COL_NORMAL          0x0u    // the normal column of the table
 #define TSDB_COL_TAG             0x1u    // the tag column type
-#define TSDB_COL_UDC   0x2u    // the user specified normal string column, it is a dummy column
+#define TSDB_COL_UDC             0x2u    // the user specified normal string column, it is a dummy column
 
 extern char *taosMsg[];
 

src/query/inc/qSqlparser.h

@@ -210,6 +210,7 @@ typedef struct tSQLExprItem {
   char *    aliasName;  // alias name, null-terminated string
 } tSQLExprItem;
 
+// todo refactor by using SArray
 typedef struct tSQLExprList {
   int32_t       nExpr;  /* Number of expressions on the list */
   int32_t       nAlloc; /* Number of entries allocated below */

src/query/src/qExecutor.c

@@ -168,7 +168,7 @@ static void buildTagQueryResult(SQInfo *pQInfo);
 static int32_t setAdditionalInfo(SQInfo *pQInfo, void *pTable, STableQueryInfo *pTableQueryInfo);
 static int32_t flushFromResultBuf(SQueryRuntimeEnv* pRuntimeEnv, SGroupResInfo* pGroupResInfo);
 
-  bool doFilterData(SQuery *pQuery, int32_t elemPos) {
+bool doFilterData(SQuery *pQuery, int32_t elemPos) {
   for (int32_t k = 0; k < pQuery->numOfFilterCols; ++k) {
     SSingleColumnFilterInfo *pFilterInfo = &pQuery->pFilterInfo[k];
 
@@ -899,7 +899,7 @@ static char *getDataBlock(SQueryRuntimeEnv *pRuntimeEnv, SArithmeticSupport *sas
       }
 
       assert(dataBlock != NULL);
-      sas->data[i] = dataBlock/* + pQuery->colList[i].bytes*/;  // start from the offset
+      sas->data[i] = dataBlock;  // start from the offset
     }
 
   } else {  // other type of query function
@@ -1583,7 +1583,7 @@ static int32_t setupQueryRuntimeEnv(SQueryRuntimeEnv *pRuntimeEnv, int16_t order
       int16_t type = pSqlFuncMsg->arg[j].argType;
       int16_t bytes = pSqlFuncMsg->arg[j].argBytes;
       if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
-        tVariantCreateFromBinary(&pCtx->param[j], pSqlFuncMsg->arg->argValue.pz, bytes, type);
+        tVariantCreateFromBinary(&pCtx->param[j], pSqlFuncMsg->arg[j].argValue.pz, bytes, type);
       } else {
         tVariantCreateFromBinary(&pCtx->param[j], (char *)&pSqlFuncMsg->arg[j].argValue.i64, bytes, type);
       }
@@ -5728,11 +5728,12 @@ static int32_t createQFunctionExprFromMsg(SQueryTableMsg *pQueryMsg, SExprInfo *
       SSchema s = tGetTableNameColumnSchema();
       type = s.type;
       bytes = s.bytes;
-    } else if (pExprs[i].base.colInfo.colId == TSDB_UD_COLUMN_INDEX) {
+    } else if (pExprs[i].base.colInfo.colId <= TSDB_UD_COLUMN_INDEX) {
+      // it is a user-defined constant value column
       assert(pExprs[i].base.functionId == TSDB_FUNC_PRJ);
 
-      type = pExprs[i].base.arg[0].argType;
-      bytes = pExprs[i].base.arg[0].argBytes;
+      type = pExprs[i].base.arg[1].argType;
+      bytes = pExprs[i].base.arg[1].argBytes;
 
       if (type == TSDB_DATA_TYPE_BINARY || type == TSDB_DATA_TYPE_NCHAR) {
         bytes += VARSTR_HEADER_SIZE;
@@ -5927,8 +5928,8 @@ static void doUpdateExprColumnIndex(SQuery *pQuery) {
       }
 
       assert(f < pQuery->numOfCols);
-    } else if (pColIndex->colId == TSDB_UD_COLUMN_INDEX) {
-      // do nothing
+    } else if (pColIndex->colId <= TSDB_UD_COLUMN_INDEX) {
+      // do nothing for user-defined constant value result columns
     } else {
       int32_t f = 0;
       for (f = 0; f < pQuery->numOfTags; ++f) {

src/query/src/qParserImpl.c

@@ -78,7 +78,7 @@ tSQLExprList *tSQLExprListAppend(tSQLExprList *pList, tSQLExpr *pNode, SSQLToken
     pList = calloc(1, sizeof(tSQLExprList));
   }
 
-  if (pList->nAlloc <= pList->nExpr) {  //
+  if (pList->nAlloc <= pList->nExpr) {
     pList->nAlloc = (pList->nAlloc << 1) + 4;
     pList->a = realloc(pList->a, pList->nAlloc * sizeof(pList->a[0]));
     if (pList->a == 0) {

tests/script/general/parser/bug.sim

@@ -40,4 +40,278 @@ sql select st1.ts, st1.f1, st2.f2 from db.st1, db.st2 where st1.t1=st2.t2 and st
 
 system_content curl -H 'Authorization: Taosd /KfeAzX/f9na8qdtNZmtONryp201ma04bEl8LcvLUd7a8qdtNZmtONryp201ma04' -d 'select st1.ts, st1.f1, st2.f2 from db.st1, db.st2 where st1.t1=st2.t2 and st1.ts=st2.ts'  127.0.0.1:7111/restful/sql
 
+print ==============select with user-defined columns
+sql select 'abc' as f, ts,f1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != @abc@ then
+  return -1
+endi
+
+if $data01 != @19-12-09 16:27:35.000@ then
+  return -1
+endi
+
+if $data02 != 1 then
+  return -1
+endi
+
+sql select 'abc', ts, f1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data01 != @19-12-09 16:27:35.000@ then
+  return -1
+endi
+
+if $data02 != 1 then
+  return -1
+endi
+
+sql select 'abc' from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != @abc@ then
+  return -1
+endi
+
+sql select 'abc' as f1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != @abc@ then
+  return -1
+endi
+
+sql select 1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 1 then
+  return -1
+endi
+
+sql select 1 as f1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 1 then
+  return -1
+endi
+
+sql select 1 as f, f1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 1 then
+  return -1
+endi
+
+if $data01 != 1 then
+  return -1
+endi
+
+sql select 1.123 as f, f1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 1.123000000 then
+  print expect 1.123000000 , actual:$data00
+  return -1
+endi
+
+sql select 1, f1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 1 then
+  return -1
+endi
+
+if $data01 != 1 then
+  return -1
+endi
+
+sql select 1.2391, f1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 1.239100000 then
+  print expect 1.239100000 actual: $data00
+  return -1
+endi
+
+if $data01 != 1 then
+  return -1
+endi
+
+print ===================== user-defined columns with agg functions
+sql select 1 as t, count(*) from t1
+if $rows != 1 then
+ return -1
+endi
+
+if $data00 != 1 then
+  return -1
+endi
+
+if $data01 != 1 then
+  return -1
+endi
+
+sql select 1, sum(f1) from t1
+if $rows != 1 then
+ return -1
+endi
+
+if $data00 != 1 then
+  return -1
+endi
+
+if $data01 != 1 then
+  return -1
+endi
+
+sql select 1,2,3, sum(f1)*99, 4,5,6,7,8,9,10 from t1
+if $rows != 1 then
+ return -1
+endi
+
+if $data00 != 1 then
+  return -1
+endi
+
+if $data01 != 2 then
+  return -1
+endi
+
+if $data02 != 3 then
+  return -1
+endi
+
+if $data03 != 99.000000000  then
+  print expect 99.000000000, actual:$data03
+  return -1
+endi
+
+sql select sum(f1)*avg(f1)+12, 1,2,3,4,5,6,7,8,9,10 from t1
+if $rows != 1 then
+ return -1
+endi
+
+if $data00 != 13.000000000 then
+  print expect 13.000000000 actual:$data00
+  return -1
+endi
+
+if $data01 != 1 then
+  return -1
+endi
+
+if $data02 != 2 then
+  return -1
+endi
+
+sql select 1.2987, f1, 'k' from t1 where f1=1
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != 1.298700000 then
+  print expect 1.298700000 actual:$data00
+  return -1
+endi
+
+if $data01 != 1 then
+  return -1
+endi
+
+if $data02 != @k@ then
+  return -1
+endi
+
+print ====================user-defined columns with union
+sql select f1, 'f1' from t1 union all select f1, 'f1' from t1;
+if $rows != 2 then
+  return -1
+endi
+
+if $data00 != 1 then
+  return -1
+endi
+
+if $data01 != @f1@ then
+  return -1
+endi
+
+if $data10 != 1 then
+  return -1
+endi
+
+if $data11 != @f1@ then
+  return -1
+endi
+
+print =====================udc with join
+sql select st1.ts, st1.f1, st2.f2, 'abc', 1.9827 from db.st1, db.st2 where st1.t1=st2.t2 and st1.ts=st2.ts
+if $rows != 1 then
+  return -1
+endi
+
+if $data00 != @19-12-09 16:27:35.000@ then
+  print expect @19-12-09 16:27:35.000@ actual:$data00
+  return -1
+endi
+
+if $data01 != 1 then
+  return -1
+endi
+
+if $data02 != 2 then
+  return -1
+endi
+
+if $data03 != @abc@ then
+  return -1
+endi
+
+if $data04 != 1.982700000 then
+  print expect 1.982700000 actual:$data04
+  return -1
+endi
+
+print ======================udc with interval
+sql select count(*), 'uuu' from t1 interval(1s) order by ts desc;
+if $rows != 1 then
+  return -1
+endi
+
+print ======================udc with tags
+sql select t1,'abc',tbname from st1
+if $rows != 1 then
+  return -1
+endi
+
+print ======================udc with arithmetic
+sql select 1+1 from t1
+if $rows != 1 then
+  return -1
+endi
+
+sql_error select from t1
+sql_error select abc from t1
+sql_error select abc as tu from t1
+
 system sh/exec.sh -n dnode1 -s stop -x SIGINT