TiDB produces different results for SELECT statements (runtime error: index out of range [0] with length 0)

[JZuming]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

Setup the environment:

tiup playground --db.binpath /path/to/latest/tidb-server &
mysql -h "127.0.0.1" -u root -P 4000 -D testdb < mysql_bk.sql

mysql_bk.sql: mysql_bk.txt

Testcase 1

mysql -h "127.0.0.1" -u root -P 4000 -D testdb

mysql> update t_smmcv set wkey = 501;
mysql> select *
from
  t_kb1xh
where 100 <= case when t_kb1xh.c_bihued = (
            select distinct
                  '1kkruc' as c0
                from
                  t_smmcv as ref_13
              ) then 101 else 57 end;

Testcase 2

mysql -h "127.0.0.1" -u root -P 4000 -D testdb

mysql> start transaction;
mysql> update t_smmcv set wkey = 501;
mysql> select *
from
  t_kb1xh
where 100 <= case when t_kb1xh.c_bihued = (
            select distinct
                  '1kkruc' as c0
                from
                  t_smmcv as ref_13
              ) then 101 else 57 end;
mysql> commit;

2. What did you expect to see? (Required)

The execution result of SELECT statements in Testcase 1 and Testcase 2 are the same.

3. What did you see instead (Required)

Output of SELECT statement in Testcase 1

ERROR 1105 (HY000): runtime error: index out of range [0] with length 0

Output of SELECT statement in Testcase 2

Empty set (0.01 sec)

Their results are different.

Information of tidb.log when test case 1 triggers runtime errors

[2022/09/27 21:12:01.779 +00:00] [INFO] [conn.go:1137] 
["command dispatched failed"] 
[conn=5830617803119407401] 
[connInfo="id:5830617803119407401, addr:127.0.0.1:56480 status:10, collation:latin1_swedish_ci, user:root"]
[command=Query] [status="inTxn:0, autocommit:1"]
[sql="select *from  t_kb1xhwhere 100 <= case when t_kb1xh.c_bihued = (            select distinct                  '1kkruc' as c0                from                  t_smmcv as ref_13              ) then 101 else 57 end"] 
[txn_mode=PESSIMISTIC] [timestamp=436289698969944066] 
[err="runtime error: index out of range [0] with length 0
github.com/pingcap/tidb/executor.recoveryHashAgg
        /home/zuming/tidb/executor/aggregate.go:451
github.com/pingcap/tidb/executor.(*HashAggPartialWorker).run.func1
        /home/zuming/tidb/executor/aggregate.go:460
runtime.gopanic
        /usr/local/go/src/runtime/panic.go:884
runtime.goPanicIndex
        /usr/local/go/src/runtime/panic.go:113
github.com/pingcap/tidb/util/chunk.(*Column).GetString
        /home/zuming/tidb/util/chunk/column.go:577
github.com/pingcap/tidb/util/chunk.Row.GetString
        /home/zuming/tidb/util/chunk/row.go:72
github.com/pingcap/tidb/expression.(*Column).EvalString
        /home/zuming/tidb/expression/column.go:434
github.com/pingcap/tidb/executor/aggfuncs.(*firstRow4String).UpdatePartialResult
        /home/zuming/tidb/executor/aggfuncs/func_first_row.go:277
github.com/pingcap/tidb/executor.(*HashAggPartialWorker).updatePartialResult
        /home/zuming/tidb/executor/aggregate.go:520
github.com/pingcap/tidb/executor.(*HashAggPartialWorker).run
        /home/zuming/tidb/executor/aggregate.go:481
runtime.goexit
        /usr/local/go/src/runtime/asm_amd64.s:1594"]

4. What is your TiDB version? (Required)

Release Version: v6.3.0-20220913
Edition: Community
Git Commit Hash: 95e09ba33c0bdb629c4d4a7a31a2e4bc1212ad2a
Git Branch: HEAD
UTC Build Time: 2022-09-24 12:55:50
GoVersion: go1.19.1
Race Enabled: false
TiKV Min Version: 6.2.0-alpha
Check Table Before Drop: false
Store: tikv