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mysql表属性、索引、约束

时间:2021-07-01 10:21:17 帮助过:2人阅读

create table item_properties_table( -> id int auto_increment primary key, -> name varchar(20) not null unique key, -> pwd varchar(48) not null, -> age tinyint default 18, -> email varchar(50) comment 电子邮件 -> ); Query OK, 0 rows affected (0.02 sec)
/*查看表结构,主要是为了查看comment*/ mysql
> show full columns from item_properties_table; +-------+-------------+-----------------+------+-----+---------+----------------+---------------------------------+--------------+ | Field | Type | Collation | Null | Key | Default | Extra | Privileges | Comment | +-------+-------------+-----------------+------+-----+---------+----------------+---------------------------------+--------------+ | id | int(11) | NULL | NO | PRI | NULL | auto_increment | select,insert,update,references | | | name | varchar(20) | utf8_general_ci | NO | UNI | NULL | | select,insert,update,references | | | pwd | varchar(48) | utf8_general_ci | NO | | NULL | | select,insert,update,references | | | age | tinyint(4) | NULL | YES | | 18 | | select,insert,update,references | | | email | varchar(50) | utf8_general_ci | YES | | NULL | | select,insert,update,references | 电子邮件 | +-------+-------------+-----------------+------+-----+---------+----------------+---------------------------------+--------------+ 5 rows in set (0.00 sec) mysql>

 

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mysql表属性、索引、约束

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