auto_increment步长如何设置
create table a(
sn bigint (20) not null auto_increment,
data varchar (500),
primary key(sn)
)auto_increment = 100;
步长为2如何写，即是sn是100,102,104,106......
[解决办法]
可以修改系统变量 auto_increment_increment
mysql> SHOW VARIABLES LIKE 'auto_inc%';+--------------------------+-------+| Variable_name | Value |+--------------------------+-------+| auto_increment_increment | 1 || auto_increment_offset | 1 |+--------------------------+-------+2 rows in set (0.00 sec)mysql> CREATE TABLE autoinc1 -> (col INT NOT NULL AUTO_INCREMENT PRIMARY KEY); Query OK, 0 rows affected (0.04 sec)mysql> SET @@auto_increment_increment=10;Query OK, 0 rows affected (0.00 sec)mysql> SHOW VARIABLES LIKE 'auto_inc%';+--------------------------+-------+| Variable_name | Value |+--------------------------+-------+| auto_increment_increment | 10 || auto_increment_offset | 1 |+--------------------------+-------+2 rows in set (0.01 sec)mysql> INSERT INTO autoinc1 VALUES (NULL), (NULL), (NULL), (NULL);Query OK, 4 rows affected (0.00 sec)Records: 4 Duplicates: 0 Warnings: 0mysql> SELECT col FROM autoinc1;+-----+| col |+-----+| 1 || 11 || 21 || 31 |+-----+4 rows in set (0.00 sec)
