diff --git a/source/common/src/tdatablock.c b/source/common/src/tdatablock.c
index 53646b84b3c..aa819ae7884 100644
--- a/source/common/src/tdatablock.c
+++ b/source/common/src/tdatablock.c
@@ -2353,27 +2353,26 @@ void trimDataBlock(SSDataBlock* pBlock, int32_t totalRows, const bool* pBoolList
   int32_t maxRows = 0;
 
   size_t numOfCols = taosArrayGetSize(pBlock->pDataBlock);
-  for (int32_t i = 0; i < numOfCols; ++i) {
-    SColumnInfoData* pDst = taosArrayGet(pBlock->pDataBlock, i);
-    // it is a reserved column for scalar function, and no data in this column yet.
-    if (pDst->pData == NULL) {
-      continue;
-    }
+  if (!pBoolList) {
+    for (int32_t i = 0; i < numOfCols; ++i) {
+      SColumnInfoData* pDst = taosArrayGet(pBlock->pDataBlock, i);
+      // it is a reserved column for scalar function, and no data in this column yet.
+      if (pDst->pData == NULL) {
+        continue;
+      }
 
-    int32_t numOfRows = 0;
-    if (IS_VAR_DATA_TYPE(pDst->info.type)) {
-      pDst->varmeta.length = 0;
+      int32_t numOfRows = 0;
+      if (IS_VAR_DATA_TYPE(pDst->info.type)) {
+        pDst->varmeta.length = 0;
+      }
     }
-  }
-
-  if (NULL == pBoolList) {
     return;
   }
-  
+
   for (int32_t i = 0; i < numOfCols; ++i) {
     SColumnInfoData* pDst = taosArrayGet(pBlock->pDataBlock, i);
     // it is a reserved column for scalar function, and no data in this column yet.
-    if (pDst->pData == NULL) {
+    if (pDst->pData == NULL || (IS_VAR_DATA_TYPE(pDst->info.type) && pDst->varmeta.length == 0)) {
       continue;
     }