From f8ff52b451df319c34be0a5b50b6451e9b4dc0cb Mon Sep 17 00:00:00 2001
From: Ganlin Zhao <ganlinzhao@hotmail.com>
Date: Fri, 8 Jul 2022 14:29:32 +0800
Subject: [PATCH] fix(query): taosd crash in stream when use max(cast())

TD-17155
---
 source/common/src/tdatablock.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/source/common/src/tdatablock.c b/source/common/src/tdatablock.c
index 38a2a70894..a6fdbb06e5 100644
--- a/source/common/src/tdatablock.c
+++ b/source/common/src/tdatablock.c
@@ -228,7 +228,7 @@ int32_t colDataMergeCol(SColumnInfoData* pColumnInfoData, uint32_t numOfRow1, ui
   uint32_t finalNumOfRows = numOfRow1 + numOfRow2;
   if (IS_VAR_DATA_TYPE(pColumnInfoData->info.type)) {
     // Handle the bitmap
-    if (finalNumOfRows > *capacity) {
+    if (finalNumOfRows > *capacity || numOfRow1 == 0) {
       char* p = taosMemoryRealloc(pColumnInfoData->varmeta.offset, sizeof(int32_t) * (numOfRow1 + numOfRow2));
       if (p == NULL) {
         return TSDB_CODE_OUT_OF_MEMORY;
@@ -262,7 +262,7 @@ int32_t colDataMergeCol(SColumnInfoData* pColumnInfoData, uint32_t numOfRow1, ui
     memcpy(pColumnInfoData->pData + oldLen, pSource->pData, len);
     pColumnInfoData->varmeta.length = len + oldLen;
   } else {
-    if (finalNumOfRows > *capacity) {
+    if (finalNumOfRows > *capacity || numOfRow1 == 0) {
       ASSERT(finalNumOfRows * pColumnInfoData->info.bytes);
       char* tmp = taosMemoryRealloc(pColumnInfoData->pData, finalNumOfRows * pColumnInfoData->info.bytes);
       if (tmp == NULL) {