diff --git a/source/dnode/vnode/inc/vnode.h b/source/dnode/vnode/inc/vnode.h
index 8f2d3bde09..9f32964fa9 100644
--- a/source/dnode/vnode/inc/vnode.h
+++ b/source/dnode/vnode/inc/vnode.h
@@ -137,8 +137,7 @@ int64_t tsdbGetNumOfRowsInMemTable(STsdbReader *pHandle);
 void   *tsdbGetIdx(SMeta *pMeta);
 void   *tsdbGetIvtIdx(SMeta *pMeta);
 
-int32_t tsdbLastRowReaderOpen(void *pVnode, int32_t type, SArray *pTableIdList, int32_t *colId, int32_t numOfCols,
-                              void **pReader);
+int32_t tsdbLastRowReaderOpen(void *pVnode, int32_t type, SArray *pTableIdList, int32_t numOfCols, void **pReader);
 int32_t tsdbRetrieveLastRow(void *pReader, SSDataBlock *pResBlock, const int32_t *slotIds);
 int32_t tsdbLastrowReaderClose(void *pReader);
 int32_t tsdbGetTableSchema(SVnode *pVnode, int64_t uid, STSchema **pSchema, int64_t *suid);
diff --git a/source/dnode/vnode/src/tsdb/tsdbCacheRead.c b/source/dnode/vnode/src/tsdb/tsdbCacheRead.c
index 150ed620bf..417c014b6e 100644
--- a/source/dnode/vnode/src/tsdb/tsdbCacheRead.c
+++ b/source/dnode/vnode/src/tsdb/tsdbCacheRead.c
@@ -32,10 +32,9 @@ typedef struct SLastrowReader {
 
 static void saveOneRow(STSRow* pRow, SSDataBlock* pBlock, SLastrowReader* pReader, const int32_t* slotIds) {
   int32_t numOfRows = pBlock->info.rows;
-  size_t  numOfCols = taosArrayGetSize(pBlock->pDataBlock);
 
   SColVal colVal = {0};
-  for (int32_t i = 0; i < numOfCols; ++i) {
+  for (int32_t i = 0; i < pReader->numOfCols; ++i) {
     SColumnInfoData* pColInfoData = taosArrayGet(pBlock->pDataBlock, i);
 
     if (slotIds[i] == -1) {
@@ -60,8 +59,7 @@ static void saveOneRow(STSRow* pRow, SSDataBlock* pBlock, SLastrowReader* pReade
   pBlock->info.rows += 1;
 }
 
-int32_t tsdbLastRowReaderOpen(void* pVnode, int32_t type, SArray* pTableIdList, int32_t* colId, int32_t numOfCols,
-                              void** pReader) {
+int32_t tsdbLastRowReaderOpen(void* pVnode, int32_t type, SArray* pTableIdList, int32_t numOfCols, void** pReader) {
   SLastrowReader* p = taosMemoryCalloc(1, sizeof(SLastrowReader));
   if (p == NULL) {
     return TSDB_CODE_OUT_OF_MEMORY;
@@ -72,6 +70,11 @@ int32_t tsdbLastRowReaderOpen(void* pVnode, int32_t type, SArray* pTableIdList,
   p->numOfCols = numOfCols;
   p->transferBuf = taosMemoryCalloc(p->numOfCols, POINTER_BYTES);
 
+  if (taosArrayGetSize(pTableIdList) == 0) {
+    *pReader = p;
+    return TSDB_CODE_SUCCESS;
+  }
+
   STableKeyInfo* pKeyInfo = taosArrayGet(pTableIdList, 0);
   p->pSchema = metaGetTbTSchema(p->pVnode->pMeta, pKeyInfo->uid, -1);
   p->pTableList = pTableIdList;
diff --git a/source/libs/executor/src/cachescanoperator.c b/source/libs/executor/src/cachescanoperator.c
index b6ad3b6cc0..7b1351a024 100644
--- a/source/libs/executor/src/cachescanoperator.c
+++ b/source/libs/executor/src/cachescanoperator.c
@@ -46,7 +46,7 @@ SOperatorInfo* createLastrowScanOperator(SLastRowScanPhysiNode* pScanNode, SRead
   pInfo->pColMatchInfo = extractColMatchInfo(pScanNode->pScanCols, pScanNode->node.pOutputDataBlockDesc, &numOfCols,
                                              COL_MATCH_FROM_COL_ID);
   int32_t* pCols = taosMemoryMalloc(numOfCols * sizeof(int32_t));
-  for (int32_t i = 0; i < numOfCols; ++i) {
+  for (int32_t i = 0; i < taosArrayGetSize(pInfo->pColMatchInfo); ++i) {
     SColMatchInfo* pColMatch = taosArrayGet(pInfo->pColMatchInfo, i);
     pCols[i] = pColMatch->colId;
   }
@@ -56,7 +56,7 @@ SOperatorInfo* createLastrowScanOperator(SLastRowScanPhysiNode* pScanNode, SRead
     goto _error;
   }
 
-  tsdbLastRowReaderOpen(readHandle->vnode, LASTROW_RETRIEVE_TYPE_ALL, pTableList, pCols, numOfCols,
+  tsdbLastRowReaderOpen(readHandle->vnode, LASTROW_RETRIEVE_TYPE_ALL, pTableList, taosArrayGetSize(pInfo->pColMatchInfo),
                         &pInfo->pLastrowReader);
   taosMemoryFree(pCols);
 
diff --git a/source/libs/executor/src/executorimpl.c b/source/libs/executor/src/executorimpl.c
index 4169ace2ab..6f4a6b805d 100644
--- a/source/libs/executor/src/executorimpl.c
+++ b/source/libs/executor/src/executorimpl.c
@@ -594,10 +594,14 @@ int32_t projectApplyFunctions(SExprInfo* pExpr, SSDataBlock* pResult, SSDataBloc
       SColumnInfoData* pColInfoData = taosArrayGet(pResult->pDataBlock, outputSlotId);
 
       int32_t offset = createNewColModel ? 0 : pResult->info.rows;
-      for (int32_t i = 0; i < pSrcBlock->info.rows; ++i) {
-        colDataAppend(pColInfoData, i + offset,
-                      taosVariantGet(&pExpr[k].base.pParam[0].param, pExpr[k].base.pParam[0].param.nType),
-                      TSDB_DATA_TYPE_NULL == pExpr[k].base.pParam[0].param.nType);
+
+      int32_t type = pExpr[k].base.pParam[0].param.nType;
+      if (TSDB_DATA_TYPE_NULL == type) {
+        colDataAppendNNULL(pColInfoData, offset, pSrcBlock->info.rows);
+      } else {
+        for (int32_t i = 0; i < pSrcBlock->info.rows; ++i) {
+          colDataAppend(pColInfoData, i + offset, taosVariantGet(&pExpr[k].base.pParam[0].param, type), false);
+        }
       }
 
       numOfRows = pSrcBlock->info.rows;