MySQL doesn't allow mutliple updates on primary key

[dyzsr]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

drop table if exists t;
create table t (a int, b int, primary key (a, b));
insert into t (1, 2);
update t t1, t t2 set t1.a=t1.a+10, t2.b=t2.b+10;

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

In MySQL 8.0.19

mysql> update t t1, t t2 set t1.a=t1.a+10, t2.b=t2.b+10;
ERROR 1706 (HY000): Primary key/partition key update is not allowed since the table is updated both as 't1' and 't2'.

3. What did you see instead (Required)

mysql> update t t1, t t2 set t1.a=t1.a+10, t2.b=t2.b+10;
Query OK, 2 rows affected (0.00 sec)
Rows matched: 2  Changed: 2  Warnings: 0

4. What is your TiDB version? (Required)

mysql> select tidb_version();
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| tidb_version()                                                                                                                                                                                                                                                                                                            |
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Release Version: v4.0.0-beta.2-1407-ge30220099
Edition: Community
Git Commit Hash: e302200999045d81b19d08d5ec240d3438674abb
Git Branch: master
UTC Build Time: 2020-10-22 11:32:06
GoVersion: go1.15
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false |
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

[SunRunAway]

/label sig/execution

[ti-srebot]

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