MySQL Tutorial custom primary key step method
CREATE TABLE IF not EXISTS ' useradmin ' (
' ID ' int (4) not NULL auto_increment,
' username ' varchar default NULL,
' userpass ' varchar default NULL,
' Logins ' int (4) Not NULL default ' 0 ' COMMENT ' landing times ',
' Logintime ' timestamp not NULL default current_timestamp on Update Current_timestamp,
' Mid ' char (1) Not NULL default ' 0 ',
PRIMARY KEY (' id ')
) Engine=innodb DEFAULT Charset=utf8 auto_increment=4;
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 useradmin VALUES (' www.111cn.net '), (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)