关于修测验UTO_INCREMENT列的默认值的测试
发布时间：2022-04-07 14:35:15 所属栏目：MySql教程 来源：互联网
导读：其实是个很简单的操作，但是忽然有人问我就是想不起来，暂且做个笔记在这里。 mysql create table test2(id int(2) AUTO_INCREMENT,name varchar(10),primary key(id)); Query OK, 0 rows affected (0.03 sec) mysql insert into test2 values(null,a),(null
|
其实是个很简单的操作，但是忽然有人问我就是想不起来，暂且做个笔记在这里。 mysql> create table test2(id int(2) AUTO_INCREMENT,name varchar(10),primary key(id)); Query OK, 0 rows affected (0.03 sec) mysql> insert into test2 values(null,'a'),(null,'b'),(null,'c'); Query OK, 3 rows affected (0.00 sec) Records: 3 Duplicates: 0 Warnings: 0 mysql> select * from test2; +----+------+ | id | name | +----+------+ | 1 | a | | 2 | b | | 3 | c | +----+------+ 3 rows in set (0.00 sec) mysql> delete from test2 where id in (2,3); Query OK, 2 rows affected (0.00 sec) mysql> select * from test2; +----+------+ | id | name | +----+------+ | 1 | a | +----+------+ 1 row in set (0.00 sec) mysql> insert into test2 values(null,'d'); Query OK, 1 row affected (0.00 sec) mysql> select * from test2; +----+------+ | id | name | +----+------+ | 1 | a | | 4 | d | +----+------+ 2 rows in set (0.00 sec) mysql> delete from test2 where id = 4; Query OK, 1 row affected (0.00 sec) mysql> alter table test2 AUTO_INCREMENT=2; Query OK, 1 row affected (0.02 sec) Records: 1 Duplicates: 0 Warnings: 0 mysql> insert into test2 values(null,'f'); Query OK, 1 row affected (0.00 sec) mysql> select * from test2; +----+------+ | id | name | +----+------+ | 1 | a | | 2 | f | +----+------+ 2 rows in set (0.00 sec) [@more@] （编辑：衡阳站长网） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |
