mysql如何增加字段
mysql增加两个字段:
(推荐教程:mysql视频教程)mysql> create table id_name(id int,name varchar(20));Query OK, 0 rows affected (0.13 sec)mysql> alter table id_name add age int,add address varchar(11);Query OK, 0 rows affected (0.13 sec)Records: 0Duplicates: 0Warnings: 0mysql> desc id_name;+---------+-------------+------+-----+---------+-------+| Field| Type| Null | Key | Default | Extra |+---------+-------------+------+-----+---------+-------+| id| int(11)| YES|| NULL||| name| varchar(20) | YES|| NULL||| age| int(11)| YES|| NULL||| address | varchar(11) | YES|| NULL||+---------+-------------+------+-----+---------+-------+4 rows in set (0.00 sec)mysql增加一个字段:alter table user add COLUMN new1 VARCHAR(20) DEFAULT NULL; //增加一个字段,默认为空alter table user add COLUMN new2 VARCHAR(20) NOT NULL;//增加一个字段,默认不能为空以上就是mysql如何增加字段的详细内容,更多请关注小潘博客其它相关文章!