Duplicate entry in global unique index report key 'UNKNOWN'

[pepezzzz]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

MySQL [test1106]> create table t_part_pk_id2(id int primary key, studentid int(10)) partition by hash(id) partitions 2;
Query OK, 0 rows affected (0.08 sec)

MySQL [test1106]> alter table t_part_pk_id2 add unique index(studentid);
Query OK, 0 rows affected (2.78 sec)

MySQL [test1106]> show create table t_part_pk_id2;
+---------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+---------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| t_part_pk_id2 | CREATE TABLE t_part_pk_id2 (
id int(11) NOT NULL,
studentid int(10) DEFAULT NULL,
PRIMARY KEY (id),
UNIQUE KEY studentid (studentid)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
PARTITION BY HASH( id )
PARTITIONS 2 |
+---------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.01 sec)

MySQL [test1106]> alter table t_part_pk_id2 alter partition p0
-> alter placement policy constraints='["+host=host71"]' role=leader replicas=1,
-> alter placement policy constraints='["-host=host71"]' role=follower replicas=2;
Query OK, 0 rows affected (0.08 sec)

MySQL [test1106]> alter table t_part_pk_id2 alter partition p1
-> alter placement policy constraints='["+host=host30"]' role=leader replicas=1,
-> alter placement policy constraints='["-host=host30"]' role=follower replicas=2;
Query OK, 0 rows affected (0.08 sec)

MySQL [test1106]> insert into t_part_pk_id1 values(1,1),(2,2),(3,3),(4,4);
ERROR 1062 (23000): Duplicate entry '7480000000000001835f698000000000000001038000000000000001' for key 'UNKNOWN'
MySQL [test1106]> insert into t_part_pk_id2 values(1,1),(2,2),(3,3),(4,4);
Query OK, 4 rows affected (0.00 sec)
Records: 4 Duplicates: 0 Warnings: 0

MySQL [test1106]> insert into t_part_pk_id2 values(1,5);
ERROR 1062 (23000): Duplicate entry '1' for key 'PRIMARY'
MySQL [test1106]> insert into t_part_pk_id2 values(5,1);
ERROR 1062 (23000): Duplicate entry '74800000000000018a5f698000000000000001038000000000000001' for key 'UNKNOWN'

by contrast,normal unique index report the real name.

MySQL [test1106]> create table t_part_pk_id3(id int primary key, studentid int(10)) ;
Query OK, 0 rows affected (0.08 sec)

MySQL [test1106]> alter table t_part_pk_id3 add unique index(studentid);
Query OK, 0 rows affected (2.78 sec)

MySQL [test1106]> show create table t_part_pk_id3;
+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| t_part_pk_id3 | CREATE TABLE t_part_pk_id3 (
id int(11) NOT NULL,
studentid int(10) DEFAULT NULL,
PRIMARY KEY (id),
UNIQUE KEY studentid (studentid)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin |
+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

MySQL [test1106]> insert into t_part_pk_id3 values(1,1),(2,2),(3,3),(4,4);
Query OK, 4 rows affected (0.00 sec)
Records: 4 Duplicates: 0 Warnings: 0

MySQL [test1106]> insert into t_part_pk_id3 values(1,5);
ERROR 1062 (23000): Duplicate entry '1' for key 'PRIMARY'
MySQL [test1106]> insert into t_part_pk_id3 values(5,1);
ERROR 1062 (23000): Duplicate entry '1' for key 'studentid'

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

the real global index name

3. What did you see instead (Required)

ERROR 1062 (23000): Duplicate entry '74800000000000018a5f698000000000000001038000000000000001' for key 'studentid'

4. What is your TiDB version? (Required)

| Release Version: v4.0.0-beta.2-1462-g280e8aa35-dirty
Edition: Community
Git Commit Hash: 280e8aa
Git Branch: master
UTC Build Time: 2020-10-31 13:35:02
GoVersion: go1.13
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false |

[crazycs520]

@tiancaiamao PTAL

[mjonss]

Global index is not yet supported, and needs to be enabled in the config file by enable-global-index = true.

[mjonss]

/component tablepartition

[bb7133]

Global partition is far from ready. I will mark it as 'won't fix' for now.