diff --git a/source/common/src/tdatablock.c b/source/common/src/tdatablock.c
index 99ff4a4a42..160756d981 100644
--- a/source/common/src/tdatablock.c
+++ b/source/common/src/tdatablock.c
@@ -1131,6 +1131,7 @@ int32_t colInfoDataEnsureCapacity(SColumnInfoData* pColumn, size_t existRows, ui
 
   if (IS_VAR_DATA_TYPE(pColumn->info.type)) {
     char* tmp = taosMemoryRealloc(pColumn->varmeta.offset, sizeof(int32_t) * numOfRows);
+
     if (tmp == NULL) {
       return TSDB_CODE_OUT_OF_MEMORY;
     }
@@ -1156,6 +1157,7 @@ int32_t colInfoDataEnsureCapacity(SColumnInfoData* pColumn, size_t existRows, ui
     if (tmp == NULL) {
       return TSDB_CODE_OUT_OF_MEMORY;
     }
+    memset(tmp + pColumn->info.bytes * existRows, 0, pColumn->info.bytes * (numOfRows - existRows));
 
     pColumn->pData = tmp;
   }
diff --git a/source/libs/scalar/src/sclvector.c b/source/libs/scalar/src/sclvector.c
index 59208de3c4..7440a6ae5b 100644
--- a/source/libs/scalar/src/sclvector.c
+++ b/source/libs/scalar/src/sclvector.c
@@ -633,7 +633,8 @@ int32_t vectorConvertImpl(const SScalarParam* pIn, SScalarParam* pOut) {
   if (IS_VAR_DATA_TYPE(inType)) {
     return vectorConvertFromVarData(pIn, pOut, inType, outType);
   }
-  
+
+  pOut->numOfRows = pIn->numOfRows;
   switch (outType) {
     case TSDB_DATA_TYPE_BOOL: {
       for (int32_t i = 0; i < pIn->numOfRows; ++i) {