From 22b53c3eceb6b0b5e5effc1b28a2a4c404117135 Mon Sep 17 00:00:00 2001
From: wangjiaming0909 <604227650@qq.com>
Date: Fri, 1 Sep 2023 16:26:42 +0800
Subject: [PATCH] fix: 1. select tag from meters partition by tag limit
 returned wrong num of rows 2. select tag from meters partition by tag
 returned wrong num of rows

---
 source/libs/executor/src/sortoperator.c        | 18 +++++++++---------
 .../system-test/2-query/interval_limit_opt.py  |  9 +++++++++
 2 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/source/libs/executor/src/sortoperator.c b/source/libs/executor/src/sortoperator.c
index 9bd0991435..a59a7bb1ea 100644
--- a/source/libs/executor/src/sortoperator.c
+++ b/source/libs/executor/src/sortoperator.c
@@ -669,8 +669,13 @@ static void doGetSortedBlockData(SMultiwayMergeOperatorInfo* pInfo, SSortHandle*
         p->info.id.groupId = tupleGroupId;
         pInfo->groupId = tupleGroupId;
       } else {
-        pInfo->prefetchedTuple = pTupleHandle;
-        break;
+        if (p->info.rows == 0) {
+          appendOneRowToDataBlock(p, pTupleHandle);
+          p->info.id.groupId = pInfo->groupId = tupleGroupId;
+        } else {
+          pInfo->prefetchedTuple = pTupleHandle;
+          break;
+        }
       }
     } else {
       appendOneRowToDataBlock(p, pTupleHandle);
@@ -715,14 +720,9 @@ SSDataBlock* getMultiwaySortedBlockData(SSortHandle* pHandle, SSDataBlock* pData
       resetLimitInfoForNextGroup(&pInfo->limitInfo);
     }
 
-    bool limitReached = applyLimitOffset(&pInfo->limitInfo, p, pTaskInfo);
-    // if limit is reached within a group, do not clear limiInfo otherwise the next block
-    // will be processed.
-    if (newgroup && limitReached) {
-      resetLimitInfoForNextGroup(&pInfo->limitInfo);
-    }
+    applyLimitOffset(&pInfo->limitInfo, p, pTaskInfo);
 
-    if (p->info.rows > 0 || limitReached) {
+    if (p->info.rows > 0) {
       break;
     }
   }
diff --git a/tests/system-test/2-query/interval_limit_opt.py b/tests/system-test/2-query/interval_limit_opt.py
index fef6e9facd..851138fed3 100644
--- a/tests/system-test/2-query/interval_limit_opt.py
+++ b/tests/system-test/2-query/interval_limit_opt.py
@@ -251,10 +251,19 @@ class TDTestCase:
         tdSql.checkData(2, 4, 9)
         tdSql.checkData(3, 4, 9)
 
+    def test_partition_by_limit_no_agg(self):
+        sql_template = 'select t1 from meters partition by t1 limit %d'
+
+        for i in range(1, 5000, 1000):
+            tdSql.query(sql_template % i)
+            tdSql.checkRows(5 * i)
+
+
     def run(self):
         self.prepareTestEnv()
         self.test_interval_limit_offset()
         self.test_interval_partition_by_slimit_limit()
+        self.test_partition_by_limit_no_agg()
 
     def stop(self):
         tdSql.close()