When DROP TABLE with multiple tables listed, and one of them does not exist, TiDB still drops all the remaining tables

[kennytm]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

use test;

create table aa(a bigint primary key); create table cc like aa;
drop table aa, bb, cc;
-- ✅ ERROR 1051 (42S02): Unknown table 'test.bb'
show tables;

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

+----------------+
| Tables_in_test |
+----------------+
| aa             |
| cc             |
...
+----------------+

3. What did you see instead (Required)

Tables aa and cc are gone

4. What is your TiDB version? (Required)

Reproduced on v6.5.5, v8.5.3 and master

[kennytm]

The existing behavior is compatible with MySQL 5.7.

However, MySQL 8.0 changed the behavior to keep aa and cc. See the MySQL 8.0.1 release note for the explanation.

I think the 8.0 behavior is safer, as users don't expect failed statements actually have side effect.