From ccd5727ba8ae605e8628e77550beff19c597cda1 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Mon, 28 Feb 2022 15:03:32 +0800
Subject: [PATCH] [td-13039] fix bug.

---
 source/libs/parser/src/queryInfoUtil.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/source/libs/parser/src/queryInfoUtil.c b/source/libs/parser/src/queryInfoUtil.c
index fc46058aa3..05aebb2cb2 100644
--- a/source/libs/parser/src/queryInfoUtil.c
+++ b/source/libs/parser/src/queryInfoUtil.c
@@ -244,6 +244,8 @@ void assignExprInfo(SExprInfo* dst, const SExprInfo* src) {
   if (src->base.numOfCols > 0) {
     dst->base.pColumns = calloc(src->base.numOfCols, sizeof(SColumn));
     memcpy(dst->base.pColumns, src->base.pColumns, sizeof(SColumn) * src->base.numOfCols);
+  } else {
+    dst->base.pColumns = NULL;
   }
 
   memset(dst->base.param, 0, sizeof(SVariant) * tListLen(dst->base.param));