Mysql8.0.22 设置默认值 DATE_FORMAT(sysdate() ,'%Y%m%d') 错误

Question

请原谅我糟糕的英语这是我的 sql

create table if not exists `test` (
    `client_id` varchar(18) not null default ' ',
    `begin_date` int not null default DATE_FORMAT(sysdate() ,'%Y%m%d') ,
    `end_date` int not null default DATE_FORMAT(sysdate() ,'%Y%m%d'),
unique index `uk_key` (`client_id` asc)
) engine = InnoDB  default charset = utf8 collate = utf8_bin comment = '';
commit;

10.3.18-MariaDB-log中执行后没有报错但是在Mysql 8.0.22中，错误

[Err] 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DATE_FORMAT(sysdate() ,'%Y%m%d'),
    `end_date` int not nu' at line

被举报；

我已经修改了@global.sql_mode和@sql_mode，但是没有用。

+-----------------------------------------------------------------------+
| @@sql_mode                                                            |
+-----------------------------------------------------------------------+
| STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION |

mysql> select @@global.sql_mode;
+-----------------------------------------------------------------------+
| @@global.sql_mode                                                     |
+-----------------------------------------------------------------------+
| STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION |
+-----------------------------------------------------------------------+

我该怎么办

Answer 1

阅读https://dev.mysql.com/doc/refman/8.0/en/data-type-defaults.html

特别是：

The default value specified in a DEFAULT clause can be a literal constant or an expression. With one exception, enclose expression default values within parentheses to distinguish them from literal constant default values.

所以在 MySQL 中，与 MariaDB 不同的是，在将表达式用作默认值时，需要将表达式放在括号内。

示例：

create table if not exists `test` (
    `client_id` varchar(18) not null default ' ',
    `begin_date` int not null default (DATE_FORMAT(sysdate() ,'%Y%m%d')),
    `end_date` int not null default (DATE_FORMAT(sysdate() ,'%Y%m%d')),
unique index `uk_key` (`client_id` asc)
) engine = InnoDB  default charset = utf8 collate = utf8_bin comment = '';

Mysql8.0.22 设置默认值 DATE_FORMAT(sysdate() ,'%Y%m%d') 错误

Mysql8.0.22 set default value DATE_FORMAT(sysdate() ,'%Y%m%d') error

mysql

default

date-format

mysql-8.0