我就是照着mysql的参考手册的说明设置的,那上面就是一个@请将手册中的例子及章节贴出以供分析。 建议下载使用原版的MYSQL的官方免费手册。o 2 rows in set (0.00 sec) o o mysql> CREATE TABLE autoinc1 (col INT NOT NULL AUTO_INCREMENT PRIMARY KEY); o Query OK, 0 rows affected (0.04 sec) o o mysql> SET @auto_increment_increment=10; o Query OK, 0 rows affected (0.00 sec) o o mysql> SHOW VARIABLES LIKE 'auto_inc%'; o +--------------------------+-------+ o | Variable_name | Value | o +--------------------------+-------+ o | auto_increment_increment | 10 | o | auto_increment_offset | 1 | o +--------------------------+-------+ o 2 rows in set (0.01 sec) o o mysql> INSERT INTO autoinc1 VALUES (NULL), (NULL), (NULL), (NULL); o Query OK, 4 rows affected (0.00 sec) o Records: 4 Duplicates: 0 Warnings: 0 o o mysql> SELECT col FROM autoinc1; o +-----+ o | col | o +-----+ o | 1 | o | 11 | o | 21 | o | 31 | o +-----+ o 4 rows in set (0.00 sec)
这不属于session和global级别当你SET @auto_increment_increment=10; 实际上是定义了一个用户变量,名字为@auto_increment_increment用show variable 是用来展示系统变量的。简单来说你执行SET @auto_increment_increment=10 跟真正的变量auto_increment_increment没有任何关系只是定义了一个名字很像,但实际名字是@auto_increment_increment的用户变量
o
o mysql> CREATE TABLE autoinc1 (col INT NOT NULL AUTO_INCREMENT PRIMARY KEY);
o Query OK, 0 rows affected (0.04 sec)
o
o mysql> SET @auto_increment_increment=10;
o Query OK, 0 rows affected (0.00 sec)
o
o mysql> SHOW VARIABLES LIKE 'auto_inc%';
o +--------------------------+-------+
o | Variable_name | Value |
o +--------------------------+-------+
o | auto_increment_increment | 10 |
o | auto_increment_offset | 1 |
o +--------------------------+-------+
o 2 rows in set (0.01 sec)
o
o mysql> INSERT INTO autoinc1 VALUES (NULL), (NULL), (NULL), (NULL);
o Query OK, 4 rows affected (0.00 sec)
o Records: 4 Duplicates: 0 Warnings: 0
o
o mysql> SELECT col FROM autoinc1;
o +-----+
o | col |
o +-----+
o | 1 |
o | 11 |
o | 21 |
o | 31 |
o +-----+
o 4 rows in set (0.00 sec)