Tidb: Insert zero date successfully in default sql mode

[wjhuang2016]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?
   If possible, provide a recipe for reproducing the error.

create table t(a date);
insert into t values('0000-00-0');

Relate issue: #8637

1. What did you expect to see?

mysql> create table t(a date);
Query OK, 0 rows affected (0.07 sec)

mysql> insert into t values('0000-00-0');
ERROR 1292 (22007): Incorrect date value: '0000-00-0' for column 'a' at row 1

1. What did you see instead?

mysql> create table t(a date);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into t values('0000-00-0');
Query OK, 1 row affected (0.00 sec)

mysql> select * from t;
+------------+
| a          |
+------------+
| 0000-00-00 |
+------------+
1 row in set (0.00 sec)

1. What version of TiDB are you using (tidb-server -V or run select tidb_version(); on TiDB)?
   master

[jackysp]

Thanks for your report, @wjhuang2016 ! Would you want to fix it?

[wjhuang2016]

Thanks for your report, @wjhuang2016 ! Would you want to fix it?

Yeah, I will try to fix it.

[jackysp]

Thanks, @wjhuang2016 !