diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index 3b91b381efef9356b3ca57bee5894b127ea4606a..e9fc27bb4e703bbdd5cf23ada7b709dc091299ac 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -65,11 +65,11 @@ static int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int3
 static int32_t insertResultField(SQueryInfo* pQueryInfo, int32_t outputIndex, SColumnList* pIdList, int16_t bytes,
                                  int8_t type, char* fieldName, SSqlExpr* pSqlExpr);
 static int32_t changeFunctionID(int32_t optr, int16_t* functionId);
-static int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSelection, bool isSTable);
+static int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSelection, bool isSTable, bool joinQuery);
 
 static bool validateIpAddress(const char* ip, size_t size);
 static bool hasUnsupportFunctionsForSTableQuery(SSqlCmd* pCmd, SQueryInfo* pQueryInfo);
-static bool functionCompatibleCheck(SQueryInfo* pQueryInfo);
+static bool functionCompatibleCheck(SQueryInfo* pQueryInfo, bool joinQuery);
 static void setColumnOffsetValueInResultset(SQueryInfo* pQueryInfo);
 
 static int32_t parseGroupbyClause(SQueryInfo* pQueryInfo, tVariantList* pList, SSqlCmd* pCmd);
@@ -1176,11 +1176,15 @@ static int32_t handleArithmeticExpr(SSqlCmd* pCmd, int32_t clauseIndex, int32_t
     columnList.num = 0;
     columnList.ids[0] = (SColumnIndex) {0, 0};
 
-    char* name = (pItem->aliasName != NULL)? pItem->aliasName:pItem->pNode->token.z;
-    size_t len = MIN(sizeof(pItem->aliasName), pItem->pNode->token.n + 1);
-    tstrncpy(pItem->aliasName, name, len);
+    char aliasName[TSDB_COL_NAME_LEN] = {0};
+    if (pItem->aliasName != NULL) {
+      tstrncpy(aliasName, pItem->aliasName, TSDB_COL_NAME_LEN);
+    } else {
+      int32_t nameLen = MIN(TSDB_COL_NAME_LEN, pItem->pNode->token.n + 1);
+      tstrncpy(aliasName, pItem->pNode->token.z, nameLen);
+    }
 
-    insertResultField(pQueryInfo, exprIndex, &columnList, sizeof(double), TSDB_DATA_TYPE_DOUBLE, pItem->aliasName, NULL);
+    insertResultField(pQueryInfo, exprIndex, &columnList, sizeof(double), TSDB_DATA_TYPE_DOUBLE, aliasName, NULL);
 
     int32_t slot = tscNumOfFields(pQueryInfo) - 1;
     SFieldSupInfo* pInfo = tscFieldInfoGetSupp(&pQueryInfo->fieldsInfo, slot);
@@ -1211,7 +1215,30 @@ static void tscInsertPrimaryTSSourceColumn(SQueryInfo* pQueryInfo, SColumnIndex*
   tscColumnListInsert(pQueryInfo->colList, &tsCol);
 }
 
-int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSelection, bool isSTable) {
+static void addProjectQueryCol(SQueryInfo* pQueryInfo, int32_t startPos, SColumnIndex* pIndex, tSQLExprItem* pItem) {
+  SSqlExpr* pExpr = doAddProjectCol(pQueryInfo, startPos, pIndex->columnIndex, pIndex->tableIndex);
+
+  STableMetaInfo* pTableMetaInfo = tscGetMetaInfo(pQueryInfo, pIndex->tableIndex);
+  STableMeta*     pTableMeta = pTableMetaInfo->pTableMeta;
+
+  SSchema* pSchema = tscGetTableColumnSchema(pTableMeta, pIndex->columnIndex);
+
+  char* colName = (pItem->aliasName == NULL) ? pSchema->name : pItem->aliasName;
+  tstrncpy(pExpr->aliasName, colName, sizeof(pExpr->aliasName));
+
+  SColumnList ids = {0};
+  ids.num = 1;
+  ids.ids[0] = *pIndex;
+
+  if (pIndex->columnIndex == TSDB_TBNAME_COLUMN_INDEX || pIndex->columnIndex == TSDB_UD_COLUMN_INDEX ||
+      pIndex->columnIndex >= tscGetNumOfColumns(pTableMeta)) {
+    ids.num = 0;
+  }
+
+  insertResultField(pQueryInfo, startPos, &ids, pExpr->resBytes, (int8_t)pExpr->resType, pExpr->aliasName, pExpr);
+}
+
+int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSelection, bool isSTable, bool joinQuery) {
   assert(pSelection != NULL && pCmd != NULL);
 
   const char* msg2 = "functions can not be mixed up";
@@ -1252,12 +1279,7 @@ int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSel
       if (code != TSDB_CODE_SUCCESS) {
         return code;
       }
-
     } else {
-      /*
-       * not support such expression
-       * e.g., select 12+5 from table_name
-       */
       return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg3);
     }
 
@@ -1270,10 +1292,22 @@ int32_t parseSelectClause(SSqlCmd* pCmd, int32_t clauseIndex, tSQLExprList* pSel
   size_t numOfSrcCols = taosArrayGetSize(pQueryInfo->colList);
   if (numOfSrcCols <= 0 && !tscQueryTags(pQueryInfo)) {
     SColumnIndex index = {0};
-    tscInsertPrimaryTSSourceColumn(pQueryInfo, &index);
+
+    // set the constant column value always attached to first table.
+    STableMetaInfo* pTableMetaInfo = tscGetTableMetaInfoFromCmd(pCmd, clauseIndex, 0);
+    SSchema* pSchema = tscGetTableColumnSchema(pTableMetaInfo->pTableMeta, PRIMARYKEY_TIMESTAMP_COL_INDEX);
+
+    // add the timestamp column into the output columns
+    int32_t numOfCols = tscSqlExprNumOfExprs(pQueryInfo);
+    tscAddSpecialColumnForSelect(pQueryInfo, numOfCols, TSDB_FUNC_PRJ, &index, pSchema, TSDB_COL_NORMAL);
+
+    SFieldSupInfo* pSupInfo = tscFieldInfoGetSupp(&pQueryInfo->fieldsInfo, numOfCols);
+    pSupInfo->visible = false;
+
+    pQueryInfo->type |= TSDB_QUERY_TYPE_PROJECTION_QUERY;
   }
 
-  if (!functionCompatibleCheck(pQueryInfo)) {
+  if (!functionCompatibleCheck(pQueryInfo, joinQuery)) {
     return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg2);
   }
 
@@ -1336,29 +1370,6 @@ SSqlExpr* doAddProjectCol(SQueryInfo* pQueryInfo, int32_t outputIndex, int32_t c
       pSchema->bytes, functionId == TSDB_FUNC_TAGPRJ);
 }
 
-static void addProjectQueryCol(SQueryInfo* pQueryInfo, int32_t startPos, SColumnIndex* pIndex, tSQLExprItem* pItem) {
-  SSqlExpr* pExpr = doAddProjectCol(pQueryInfo, startPos, pIndex->columnIndex, pIndex->tableIndex);
-
-  STableMetaInfo* pTableMetaInfo = tscGetMetaInfo(pQueryInfo, pIndex->tableIndex);
-  STableMeta*     pTableMeta = pTableMetaInfo->pTableMeta;
-  
-  SSchema* pSchema = tscGetTableColumnSchema(pTableMeta, pIndex->columnIndex);
-
-  char* colName = (pItem->aliasName == NULL) ? pSchema->name : pItem->aliasName;
-  tstrncpy(pExpr->aliasName, colName, sizeof(pExpr->aliasName));
-  
-  SColumnList ids = {0};
-  ids.num = 1;
-  ids.ids[0] = *pIndex;
-
-  if (pIndex->columnIndex == TSDB_TBNAME_COLUMN_INDEX || pIndex->columnIndex == TSDB_UD_COLUMN_INDEX ||
-      pIndex->columnIndex >= tscGetNumOfColumns(pTableMeta)) {
-    ids.num = 0;
-  }
-
-  insertResultField(pQueryInfo, startPos, &ids, pExpr->resBytes, (int8_t)pExpr->resType, pExpr->aliasName, pExpr);
-}
-
 SSqlExpr* tscAddSpecialColumnForSelect(SQueryInfo* pQueryInfo, int32_t outputColIndex, int16_t functionId,
                                   SColumnIndex* pIndex, SSchema* pColSchema, int16_t flag) {
   SSqlExpr* pExpr = tscSqlExprInsert(pQueryInfo, outputColIndex, functionId, pIndex, pColSchema->type,
@@ -1837,10 +1848,11 @@ int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int32_t col
 
           for (int32_t i = 0; i < tscGetNumOfColumns(pTableMetaInfo->pTableMeta); ++i) {
             SColumnIndex index = {.tableIndex = j, .columnIndex = i};
-            if (setExprInfoForFunctions(pCmd, pQueryInfo, pSchema, functionID, pItem->aliasName, colIndex + i + j, &index) !=
-                0) {
+            if (setExprInfoForFunctions(pCmd, pQueryInfo, pSchema, functionID, pItem->aliasName, colIndex, &index) != 0) {
               return TSDB_CODE_TSC_INVALID_SQL;
             }
+
+            colIndex++;
           }
 
           numOfFields += tscGetNumOfColumns(pTableMetaInfo->pTableMeta);
@@ -2513,7 +2525,7 @@ bool hasUnsupportFunctionsForSTableQuery(SSqlCmd* pCmd, SQueryInfo* pQueryInfo)
   return false;
 }
 
-static bool functionCompatibleCheck(SQueryInfo* pQueryInfo) {
+static bool functionCompatibleCheck(SQueryInfo* pQueryInfo, bool joinQuery) {
   int32_t startIdx = 0;
   
   SSqlExpr* pExpr = tscSqlExprGet(pQueryInfo, startIdx);
@@ -2545,6 +2557,10 @@ static bool functionCompatibleCheck(SQueryInfo* pQueryInfo) {
     if (functionCompatList[functionId] != factor) {
       return false;
     }
+
+    if (functionId == TSDB_FUNC_LAST_ROW && joinQuery) {
+      return false;
+    }
   }
 
   return true;
@@ -5863,7 +5879,7 @@ int32_t doCheckForStream(SSqlObj* pSql, SSqlInfo* pInfo) {
   }
 
   bool isSTable = UTIL_TABLE_IS_SUPER_TABLE(pTableMetaInfo);
-  if (parseSelectClause(&pSql->cmd, 0, pQuerySql->pSelection, isSTable) != TSDB_CODE_SUCCESS) {
+  if (parseSelectClause(&pSql->cmd, 0, pQuerySql->pSelection, isSTable, false) != TSDB_CODE_SUCCESS) {
     return TSDB_CODE_TSC_INVALID_SQL;
   }
 
@@ -6046,7 +6062,8 @@ int32_t doCheckForQuery(SSqlObj* pSql, SQuerySQL* pQuerySql, int32_t index) {
     return TSDB_CODE_TSC_INVALID_SQL;
   }
 
-  if (parseSelectClause(pCmd, index, pQuerySql->pSelection, isSTable) != TSDB_CODE_SUCCESS) {
+  int32_t joinQuery = (pQuerySql->from != NULL && pQuerySql->from->nExpr > 2);
+  if (parseSelectClause(pCmd, index, pQuerySql->pSelection, isSTable, joinQuery) != TSDB_CODE_SUCCESS) {
     return TSDB_CODE_TSC_INVALID_SQL;
   }
 
@@ -6080,6 +6097,9 @@ int32_t doCheckForQuery(SSqlObj* pSql, SQuerySQL* pQuerySql, int32_t index) {
     }
   } else {  // set the time rang
     pQueryInfo->window = TSWINDOW_INITIALIZER;
+    if (pQuerySql->from->nExpr > 2) { // it is a join query, no wher clause is not allowed.
+      return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), "condition missing for join query ");
+    }
   }
 
   // user does not specified the query time window, twa is not allowed in such case.
diff --git a/src/common/src/tname.c b/src/common/src/tname.c
index 2eda5953a3e5c9e83a5986de71baf173579cb890..960cc7d7251d95c37e7011e68bc47b0c6ae012e0 100644
--- a/src/common/src/tname.c
+++ b/src/common/src/tname.c
@@ -62,8 +62,10 @@ SSchema tGetUserSpecifiedColumnSchema(tVariant* pVal, SStrToken* exprStr, const
   if (name != NULL) {
     tstrncpy(s.name, name, sizeof(s.name));
   } else {
-    size_t len = MIN(sizeof(s.name), exprStr->n + 1);
-    tstrncpy(s.name, exprStr->z, len);
+    size_t len = strdequote(exprStr->z);
+    size_t tlen = MIN(sizeof(s.name), len + 1);
+
+    tstrncpy(s.name, exprStr->z, tlen);
   }
 
   return s;
diff --git a/src/query/src/qExecutor.c b/src/query/src/qExecutor.c
index 5baa3f2bf84045f78ea642e34ced7391bdbafe19..19324bc2cb79df630bf985ff67e6f7c95c540fe8 100644
--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -1770,13 +1770,20 @@ static bool needReverseScan(SQuery *pQuery) {
   return false;
 }
 
+/**
+ * The following 4 kinds of query are treated as the tags query
+ * tagprj, tid_tag query, count(tbname), 'abc' (user defined constant value column) query
+ */
 static bool onlyQueryTags(SQuery* pQuery) {
   for(int32_t i = 0; i < pQuery->numOfOutput; ++i) {
     SExprInfo* pExprInfo = &pQuery->pSelectExpr[i];
 
     int32_t functionId = pExprInfo->base.functionId;
-    if (functionId != TSDB_FUNC_TAGPRJ && functionId != TSDB_FUNC_TID_TAG &&
-        (!(functionId == TSDB_FUNC_COUNT && pExprInfo->base.colInfo.colId == TSDB_TBNAME_COLUMN_INDEX))) {
+
+    if (functionId != TSDB_FUNC_TAGPRJ &&
+        functionId != TSDB_FUNC_TID_TAG &&
+        (!(functionId == TSDB_FUNC_COUNT && pExprInfo->base.colInfo.colId == TSDB_TBNAME_COLUMN_INDEX)) &&
+        (!(functionId == TSDB_FUNC_PRJ && pExprInfo->base.colInfo.flag == TSDB_COL_UDC))) {
       return false;
     }
   }
@@ -6835,6 +6842,10 @@ static void buildTagQueryResult(SQInfo* pQInfo) {
       char *data = NULL, *dst = NULL;
       int16_t type = 0, bytes = 0;
       for(int32_t j = 0; j < pQuery->numOfOutput; ++j) {
+        // not assign value in case of user defined constant output column
+        if (pExprInfo[j].base.colInfo.flag == TSDB_COL_UDC) {
+          continue;
+        }
 
         if (pExprInfo[j].base.colInfo.colId == TSDB_TBNAME_COLUMN_INDEX) {
           bytes = tbnameSchema.bytes;
diff --git a/src/query/src/qParserImpl.c b/src/query/src/qParserImpl.c
index 0b5408f793f7f6d3de06f53dd81bcca08d8fe8a8..733459c6fe8d92786ec9d9d37d2bceb0eadc4bca 100644
--- a/src/query/src/qParserImpl.c
+++ b/src/query/src/qParserImpl.c
@@ -167,6 +167,8 @@ tSQLExpr *tSQLExprCreateFunction(tSQLExprList *pList, SStrToken *pFuncToken, SSt
 
   pExpr->operand.n = len;  // raw field name
   pExpr->operand.type = pFuncToken->type;
+
+  pExpr->token = pExpr->operand;
   return pExpr;
 }
 
diff --git a/tests/script/general/parser/constCol.sim b/tests/script/general/parser/constCol.sim
index 889fe8304281a9d22f35765faa268b4e78564c9f..a196ba2b505abc59868eccc30c32989f77eaefd6 100644
--- a/tests/script/general/parser/constCol.sim
+++ b/tests/script/general/parser/constCol.sim
@@ -34,6 +34,9 @@ sql create table t1 using st1 tags(1);
 sql create table t2 using st2 tags(1);
 
 sql insert into t1 values(1575880055000, 1);
+sql insert into t1 values(1575880059000, 1);
+sql insert into t1 values(1575880069000, 1);
+
 sql insert into t2 values(1575880055000, 2);
 
 sql select st1.ts, st1.f1, st2.f2 from db.st1, db.st2 where st1.t1=st2.t2 and st1.ts=st2.ts
@@ -42,7 +45,7 @@ system_content curl -H 'Authorization: Taosd /KfeAzX/f9na8qdtNZmtONryp201ma04bEl
 
 print ==============select with user-defined columns
 sql select 'abc' as f, ts,f1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -59,7 +62,7 @@ if $data02 != 1 then
 endi
 
 sql select 'abc', ts, f1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -71,8 +74,12 @@ if $data02 != 1 then
   return -1
 endi
 
+if $data10 != @abc@ then
+  return -1
+endi
+
 sql select 'abc' from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -81,7 +88,7 @@ if $data00 != @abc@ then
 endi
 
 sql select 'abc' as f1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -90,7 +97,7 @@ if $data00 != @abc@ then
 endi
 
 sql select 1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -98,8 +105,16 @@ if $data00 != 1 then
   return -1
 endi
 
+if $data10 != 1 then
+  return -1
+endi
+
+if $data20 != 1 then
+  return -1
+endi
+
 sql select 1 as f1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -108,7 +123,7 @@ if $data00 != 1 then
 endi
 
 sql select 1 as f, f1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -121,7 +136,7 @@ if $data01 != 1 then
 endi
 
 sql select 1.123 as f, f1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -130,8 +145,13 @@ if $data00 != 1.123000000 then
   return -1
 endi
 
+if $data10 != 1.123000000 then
+  print expect 1.123000000 , actual:$data10
+  return -1
+endi
+
 sql select 1, f1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -143,8 +163,12 @@ if $data01 != 1 then
   return -1
 endi
 
+if $data10 != 1 then
+  return -1
+endi
+
 sql select 1.2391, f1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -153,6 +177,11 @@ if $data00 != 1.239100000 then
   return -1
 endi
 
+if $data10 != 1.239100000 then
+  print expect 1.239100000 actual: $data00
+  return -1
+endi
+
 if $data01 != 1 then
   return -1
 endi
@@ -167,7 +196,7 @@ if $data00 != 1 then
   return -1
 endi
 
-if $data01 != 1 then
+if $data01 != 3 then
   return -1
 endi
 
@@ -180,7 +209,7 @@ if $data00 != 1 then
   return -1
 endi
 
-if $data01 != 1 then
+if $data01 != 3 then
   return -1
 endi
 
@@ -201,8 +230,8 @@ if $data02 != 3 then
   return -1
 endi
 
-if $data03 != 99.000000000  then
-  print expect 99.000000000, actual:$data03
+if $data03 != 297.000000000  then
+  print expect 297.000000000, actual:$data03
   return -1
 endi
 
@@ -211,8 +240,8 @@ if $rows != 1 then
  return -1
 endi
 
-if $data00 != 13.000000000 then
-  print expect 13.000000000 actual:$data00
+if $data00 != 15.000000000 then
+  print expect 15.000000000 actual:$data00
   return -1
 endi
 
@@ -225,7 +254,7 @@ if $data02 != 2 then
 endi
 
 sql select 1.2987, f1, 'k' from t1 where f1=1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -244,7 +273,7 @@ endi
 
 print ====================user-defined columns with union
 sql select f1, 'f1' from t1 union all select f1, 'f1' from t1;
-if $rows != 2 then
+if $rows != 6 then
   return -1
 endi
 
@@ -294,7 +323,7 @@ endi
 
 print ======================udc with interval
 sql select count(*), 'uuu' from t1 interval(1s) order by ts desc;
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi
 
@@ -304,9 +333,17 @@ if $rows != 1 then
   return -1
 endi
 
+if $data01 != @abc@ then
+  return -1
+endi
+
+if $data02 != @t1@ then
+  return -1
+endi
+
 print ======================udc with arithmetic
 sql select 1+1 from t1
-if $rows != 1 then
+if $rows != 3 then
   return -1
 endi