📅  最后修改于: 2022-03-11 15:05:17.299000             🧑  作者: Mango
This is disabled by default in recent versions.
mysql> set @@sql_auto_is_null:=default;
Query OK, 0 rows affected (0.00 sec)
mysql> select @@sql_auto_is_null,@@version;
+--------------------+-----------+
| @@sql_auto_is_null | @@version |
+--------------------+-----------+
| 0 | 5.8.0-m17 |
+--------------------+-----------+
1 row in set (0.00 sec)