From b9927cce1408760372f61b7168816318efaffaf3 Mon Sep 17 00:00:00 2001
From: factosea <285808407@qq.com>
Date: Mon, 29 Jan 2024 16:04:08 +0800
Subject: [PATCH] fix: count error on tag which is null

---
 source/common/src/tdatablock.c          | 1 +
 source/libs/executor/src/scanoperator.c | 4 ++--
 source/libs/function/src/builtinsimpl.c | 6 ++++--
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/source/common/src/tdatablock.c b/source/common/src/tdatablock.c
index 5382259899..8739068432 100644
--- a/source/common/src/tdatablock.c
+++ b/source/common/src/tdatablock.c
@@ -224,6 +224,7 @@ static int32_t doCopyNItems(struct SColumnInfoData* pColumnInfoData, int32_t cur
 
 int32_t colDataSetNItems(SColumnInfoData* pColumnInfoData, uint32_t currentRow, const char* pData, uint32_t numOfRows,
                          bool trimValue) {
+  if (currentRow >= numOfRows) return TSDB_CODE_SUCCESS;
   int32_t len = pColumnInfoData->info.bytes;
   if (IS_VAR_DATA_TYPE(pColumnInfoData->info.type)) {
     len = varDataTLen(pData);
diff --git a/source/libs/executor/src/scanoperator.c b/source/libs/executor/src/scanoperator.c
index 9243f385d0..1b69bcce94 100644
--- a/source/libs/executor/src/scanoperator.c
+++ b/source/libs/executor/src/scanoperator.c
@@ -684,7 +684,7 @@ void markGroupProcessed(STableScanInfo* pInfo, uint64_t groupId) {
 static SSDataBlock* getOneRowResultBlock(SExecTaskInfo* pTaskInfo, STableScanBase* pBase, SSDataBlock* pBlock,
                                          const STableKeyInfo* tbInfo) {
   blockDataEmpty(pBlock);
-  pBlock->info.rows = 1;
+  pBlock->info.rows = 0;
   pBlock->info.id.uid = tbInfo->uid;
   pBlock->info.id.groupId = tbInfo->groupId;
 
@@ -696,7 +696,7 @@ static SSDataBlock* getOneRowResultBlock(SExecTaskInfo* pTaskInfo, STableScanBas
   }
 
   // set tag/tbname
-  doSetTagColumnData(pBase, pBlock, pTaskInfo, pBlock->info.rows);
+  doSetTagColumnData(pBase, pBlock, pTaskInfo, 1);
   return pBlock;
 }
 
diff --git a/source/libs/function/src/builtinsimpl.c b/source/libs/function/src/builtinsimpl.c
index 000f634fe5..fc1fe29332 100644
--- a/source/libs/function/src/builtinsimpl.c
+++ b/source/libs/function/src/builtinsimpl.c
@@ -2338,6 +2338,8 @@ int32_t lastFunction(SqlFunctionCtx* pCtx) {
     return TSDB_CODE_SUCCESS;
   }
 
+  if(pInput->totalRows == 0) return TSDB_CODE_SUCCESS;
+
   SColumnDataAgg* pColAgg = (pInput->colDataSMAIsSet) ? pInput->pColumnDataAgg[0] : NULL;
 
   TSKEY startKey = getRowPTs(pInput->pPTS, 0);
@@ -2647,7 +2649,7 @@ int32_t lastRowFunction(SqlFunctionCtx* pCtx) {
   int32_t bytes = pInputCol->info.bytes;
   pInfo->bytes = bytes;
 
-  if (IS_NULL_TYPE(type)) {
+  if (IS_NULL_TYPE(type) || 0 == pInput->totalRows) {
     return TSDB_CODE_SUCCESS;
   }
 
@@ -6022,7 +6024,7 @@ int32_t groupKeyFunction(SqlFunctionCtx* pCtx) {
     goto _group_key_over;
   }
 
-  if (colDataIsNull_s(pInputCol, startIndex)) {
+  if (pInputCol->pData == NULL || colDataIsNull_s(pInputCol, startIndex)) {
     pInfo->isNull = true;
     pInfo->hasResult = true;
     goto _group_key_over;