diff --git a/src/query/src/qUtil.c b/src/query/src/qUtil.c
index 71ee0f24352c494d3eb10d5133528b7aa0dcef8b..46079e6830f91712490bcdcdd61de4902a3a5015 100644
--- a/src/query/src/qUtil.c
+++ b/src/query/src/qUtil.c
@@ -246,7 +246,7 @@ void interResToBinary(SBufferWriter* bw, SArray* pRes, int32_t tagLen) {
     tbufWriteUint32(bw, numOfCols);
     for(int32_t j = 0; j < numOfCols; ++j) {
       SStddevInterResult* p = taosArrayGet(pOne->pResult, j);
-      uint32_t numOfRows = taosArrayGetSize(p->pResult);
+      uint32_t numOfRows = (uint32_t) taosArrayGetSize(p->pResult);
 
       tbufWriteUint16(bw, p->colId);
       tbufWriteUint32(bw, numOfRows);