Wrong result when IndexMerge is used with virtual column

[guo-shaoge]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

drop table if exists t1;
create table t1(c1 int, c2 int, c3 int as (c1 + c2), key(c1), key(c2), key(c3));
insert into t1(c1, c2) values(1, 1);
select /*+ use_index_merge(t1) */ * from t1 where c1 < -10 or c2 < 10 and reverse(c3) = '2';  

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

mysql> select * from t1 where c1 < -10 or c2 < 10 and reverse(c3) = '2';
+------+------+------+
| c1   | c2   | c3   |
+------+------+------+
|    1 |    1 |    2 |
+------+------+------+
1 row in set (0.01 sec)

3. What did you see instead (Required)

mysql> select /*+ use_index_merge(t1) */ * from t1 where c1 < -10 or c2 < 10 and reverse(c3) = '2';
Empty set (0.01 sec)

4. What is your TiDB version? (Required)

mysql> select tidb_version();
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| tidb_version()
                          |
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Release Version: v5.4.0-alpha-241-g7a8c7f89ce
Edition: Community
Git Commit Hash: 7a8c7f89cebe0e5596415a6106b1345cec9cfa27
Git Branch: master
UTC Build Time: 2021-11-28 02:32:15
GoVersion: go1.16.4
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false |
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

[guo-shaoge]

fixed in #30341