Incorrect weekday behaviour

[breezewish]

Bug Report

set sql_mode = 'ALLOW_INVALID_DATES';

create table t (col datetime);

insert into t values ('2004-04-31');

select weekday(col) from t;

MySQL:

mysql> select weekday(col) from t;
+--------------+
| weekday(col) |
+--------------+
|            5 |
+--------------+
1 row in set (0.00 sec)

TiDB:

mysql> select weekday(col) from t;
+--------------+
| weekday(col) |
+--------------+
|            6 |
+--------------+
1 row in set (0.00 sec)

[Ishiihara]

@ngaut @breeswish Can you assign this issue to me?

[Deardrops]

@Ishiihara you could review the PR #10864 for this issue.

[zz-jason]

fixed by #10864