refactor: do some internal refactor.

source/libs/executor/src/executorimpl.c

@@ -4581,7 +4581,7 @@ static SResSchema createResSchema(int32_t type, int32_t bytes, int32_t slotId, i
   return s;
 }
 
-static SColumn* createColumn(int32_t blockId, int32_t slotId, SDataType* pType) {
+static SColumn* createColumn(int32_t blockId, int32_t slotId, int32_t colId, SDataType* pType) {
   SColumn* pCol = taosMemoryCalloc(1, sizeof(SColumn));
   if (pCol == NULL) {
     terrno = TSDB_CODE_OUT_OF_MEMORY;
@@ -4589,9 +4589,10 @@ static SColumn* createColumn(int32_t blockId, int32_t slotId, SDataType* pType)
   }
 
   pCol->slotId = slotId;
-  pCol->bytes = pType->bytes;
-  pCol->type = pType->type;
-  pCol->scale = pType->scale;
+  pCol->colId  = colId;
+  pCol->bytes  = pType->bytes;
+  pCol->type   = pType->type;
+  pCol->scale  = pType->scale;
   pCol->precision = pType->precision;
   pCol->dataBlockId = blockId;
 
@@ -4634,7 +4635,7 @@ SExprInfo* createExprInfo(SNodeList* pNodeList, SNodeList* pGroupKeys, int32_t*
       SDataType* pType = &pColNode->node.resType;
       pExp->base.resSchema = createResSchema(pType->type, pType->bytes, pTargetNode->slotId, pType->scale,
                                              pType->precision, pColNode->colName);
-      pExp->base.pParam[0].pCol = createColumn(pColNode->dataBlockId, pColNode->slotId, pType);
+      pExp->base.pParam[0].pCol = createColumn(pColNode->dataBlockId, pColNode->slotId, pColNode->colId, pType);
       pExp->base.pParam[0].type = FUNC_PARAM_TYPE_COLUMN;
     } else if (type == QUERY_NODE_VALUE) {
       pExp->pExpr->nodeType = QUERY_NODE_VALUE;
@@ -4686,7 +4687,7 @@ SExprInfo* createExprInfo(SNodeList* pNodeList, SNodeList* pGroupKeys, int32_t*
           SColumnNode* pcn = (SColumnNode*)p1;
 
           pExp->base.pParam[j].type = FUNC_PARAM_TYPE_COLUMN;
-          pExp->base.pParam[j].pCol = createColumn(pcn->dataBlockId, pcn->slotId, &pcn->node.resType);
+          pExp->base.pParam[j].pCol = createColumn(pcn->dataBlockId, pcn->slotId, pcn->colId, &pcn->node.resType);
         } else if (p1->type == QUERY_NODE_VALUE) {
           SValueNode* pvn = (SValueNode*)p1;
           pExp->base.pParam[j].type = FUNC_PARAM_TYPE_VALUE;

source/libs/executor/src/scanoperator.c

@@ -13,8 +13,8 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include "filter.h"
 #include "function.h"
+#include "filter.h"
 #include "functionMgt.h"
 #include "os.h"
 #include "querynodes.h"
@@ -1348,35 +1348,33 @@ static SSDataBlock* doTagScan(SOperatorInfo* pOperator) {
   char        str[512] = {0};
   int32_t     count = 0;
   SMetaReader mr = {0};
+  metaReaderInit(&mr, pInfo->readHandle.meta, 0);
 
   while (pInfo->curPos < pInfo->pTableGroups->numOfTables && count < pOperator->resultInfo.capacity) {
     STableKeyInfo* item = taosArrayGet(pa, pInfo->curPos);
+    metaGetTableEntryByUid(&mr, item->uid);
 
     for (int32_t j = 0; j < pOperator->numOfExprs; ++j) {
       SColumnInfoData* pDst = taosArrayGet(pRes->pDataBlock, pExprInfo[j].base.resSchema.slotId);
 
       // refactor later
       if (fmIsScanPseudoColumnFunc(pExprInfo[j].pExpr->_function.functionId)) {
-        metaReaderInit(&mr, pInfo->readHandle.meta, 0);
-        metaGetTableEntryByUid(&mr, item->uid);
-
         STR_TO_VARSTR(str, mr.me.name);
-        metaReaderClear(&mr);
-
         colDataAppend(pDst, count, str, false);
-        //        data = tsdbGetTableTagVal(item->pTable, pExprInfo[j].base.pColumns->info.colId, type, bytes);
-        //        dst  = pColInfo->pData + count * pExprInfo[j].base.resSchema.bytes;
-        //        doSetTagValueToResultBuf(dst, data, type, bytes);
+      } else { // it is a tag value
+        const char* p = metaGetTableTagVal(&mr.me, pExprInfo[j].base.pParam[0].pCol->colId);
+        colDataAppend(pDst, count, p, (p == NULL));
       }
-
-      count += 1;
     }
 
+    count += 1;
     if (++pInfo->curPos >= pInfo->pTableGroups->numOfTables) {
       pOperator->status = OP_EXEC_DONE;
     }
   }
 
+  metaReaderClear(&mr);
+
   // qDebug("QInfo:0x%"PRIx64" create tag values results completed, rows:%d", GET_TASKID(pRuntimeEnv), count);
   if (pOperator->status == OP_EXEC_DONE) {
     setTaskStatus(pTaskInfo, TASK_COMPLETED);