diff --git a/source/common/src/tdatablock.c b/source/common/src/tdatablock.c
index 887a11083153..5188b1e27c3b 100644
--- a/source/common/src/tdatablock.c
+++ b/source/common/src/tdatablock.c
@@ -549,6 +549,7 @@ SSDataBlock* blockDataExtractBlock(SSDataBlock* pBlock, int32_t startIndex, int3
   pDst->info = pBlock->info;
   pDst->info.rows = 0;
   pDst->info.capacity = 0;
+  pDst->info.rowSize = 0;
   size_t numOfCols = taosArrayGetSize(pBlock->pDataBlock);
   for (int32_t i = 0; i < numOfCols; ++i) {
     SColumnInfoData  colInfo = {0};