sorting index merge result in partition union reports 'index out of range'

[wjhuang2016]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

CREATE TABLE `t` (
  `col_5` text NOT NULL,
  `col_6` tinyint(3) unsigned DEFAULT NULL,
  `col_7` float DEFAULT '4779.165058537128',
  `col_8` smallint(6) NOT NULL DEFAULT '-24790',
  `col_9` date DEFAULT '2031-01-15',
  `col_37` int(11) DEFAULT '1350204687',
  PRIMARY KEY (`col_5`(6),`col_8`) /*T![clustered_index] NONCLUSTERED */,
  UNIQUE KEY `idx_6` (`col_9`,`col_7`,`col_8`),
  KEY `idx_8` (`col_8`,`col_6`,`col_5`(6),`col_9`,`col_7`),
  KEY `idx_9` (`col_9`,`col_7`,`col_8`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
PARTITION BY RANGE ( `col_8` ) (
  PARTITION `p0` VALUES LESS THAN (-17650),
  PARTITION `p1` VALUES LESS THAN (-13033),
  PARTITION `p2` VALUES LESS THAN (2521),
  PARTITION `p3` VALUES LESS THAN (7510)
);
insert into t values ("", NULL, 6304.0146, -24790, "2031-01-15", 1350204687);
select  var_samp(col_7) aggCol from (select  /*+ use_index_merge( t ) */ * from t where t.col_9 in ( '2002-06-22' ) or t.col_5 in ( 'PkfzI'  ) or t.col_8 in ( -24874 ) and t.col_6 > null and t.col_5 > 'r' and t.col_9 in ( '1979-09-04' ) and t.col_7 < 8143.667552769195 or t.col_5 in ( 'iZhfEjRWci' , 'T' , ''  ) or t.col_9 <> '1976-09-11' and t.col_7 = 8796.436181615773 and
t.col_8 = 7372 order by col_5,col_8  ) ordered_tbl group by col_6;

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

No panic

3. What did you see instead (Required)

mysql> select  var_samp(col_7) aggCol from (select  /*+ use_index_merge( t ) */ * from t where t.col_9 in ( '2002-06-22' ) or t.col_5 in ( 'PkfzI'  ) or t.col_8 in ( -24874 ) and t.col_6 > null and t.col_5 > 'r' and t.col_9 in ( '1979-09-04' ) and t.col_7 < 8143.667552769195 or t.col_5 in ( 'iZhfEjRWci' , 'T' , ''  ) or t.col_9 <> '1976-09-11' and t.col_7 = 8796.436181615773 and
t.col_8 = 7372 order by col_5,col_8  ) ordered_tbl group by col_6;
ERROR 1105 (HY000): runtime error: index out of range [5] with length 5

4. What is your TiDB version? (Required)

master

[tangenta]

Minimal reproducible case:

drop table if exists t;
create table t (a int, b int, index(a), index(b)) partition by hash (a) partitions 2;
insert into t values (1, 5);
select /*+ use_index_merge( t ) */ * from t where a in (3) or b in (5) order by a;

This bug occurs when the following conditions are satisfied:

1. The table contains _tidb_rowid
2. The query has partition_union operator(partitions)
3. The query has index_merge operator
4. The query has sort operator(order by)
5. The table contains matched data

Introduced in #18699.

[ti-srebot]

Please edit this comment or add a new comment to complete the following information

Bug

1. Root Cause Analysis (RCA) (optional)

The schema is inconsistent between Sort operator and IndexMerge operator. For details, see #23936.

2. Symptom (optional)

"index out of range" error or "invalid encoded key" error.

3. All Trigger Conditions (optional)

1. The table contains _tidb_rowid
2. The query has partition_union operator(partitions)
3. The query has index_merge operator
4. The query has sort operator(order by)
5. The table contains matched data

4. Workaround (optional)

5. Affected versions

[v5.0.0:v5.0.1]

6. Fixed versions

v5.0.2