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MySQL服务器的SQL模式_MySQL

Jun 01, 2016 pm 01:37 PM
mysql client server Configuration file

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sql_mode的系统变量可以调控MySQL的SQL模式

任何一个客户端可以在不影响其它客户端的情况下改变MySQL服务器对自己的反应

MySQL服务器的SQL模式_MySQL

 

如果想在MySQL启动时设置SQL模式,可以在mysql配置文件中添加sql_mode选项

sql-mode=”TRADITIONAL”

如果在运行过程中修改SQL模式,则可以使用如下命令

setsql_mode="TRADITIONAL";

Client1

 

mysql> show variables like "sql_mode";

 

+---------------+-------+

 

| Variable_name | Value |

 

+---------------+-------+

 

| sql_mode||

 

+---------------+-------+

 

1 row in set (0.00 sec)

 

mysql> set sql_mode="TRADITIONAL";

 

Query OK, 0 rows affected(0.23 sec)

 

mysql> show variables like "sql_mode";

 

+---------------+---------------------------------------------------------------------------------------------------------

 

|Variable_name |Value |

 

+---------------+-----------------------------------------------------------------------------------------------------------

 

|sql_mode|STRICT_TRANS_TABLES,STRICT_ALL_TABLES,NO_ZERO_IN_DATE,NO_ZERO
_DATE,ERROR_FOR_pISION_BY_ZERO,TRADITIONAL,NO_AUTO_CREATE_USER,NO_
ENGINE_SUBSTITUTION|

 

+---------------+------------------------------------------------------------------------------------------------------------

 

1 rowin set (0.00 sec)

 

mysql>

Client2

Client1已经修改了SQL模式,但是Client2的SQL模式没有改变,这就说明客户端之间的模式修改
是互相不影响的

 

mysql> show variables like "sql_mode";

 

+---------------+-------+

 

| Variable_name | Value |

 

+---------------+-------+

 

| sql_mode||

 

+---------------+-------+

 

1 row in set (0.00 sec)

 

mysql>

设置全局变量(设置全局变量设置,需要加上GLOBAL关键字,需要SUPER权限)

mysql> set globalsql_mode="traditional";

Query OK, 0 rows affected(0.02 sec)
 

select@@session.sql_mode --》查看当前会话sql模式

select@@GLOBAL.sql_mode --》查看系统会话sql模式

设置全局变量后,新连接的客户端默认的就是全局的SQL模式
 

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