• mysql 数据类型 枚举类型与集合类型


    字段的值只能在给定范围中选择,如单选框,多选框

    enum 单选 只能在给定的范围内选一个值,如性别 sex 男male/女female

     

    set 多选 在给定的范围内可以选择一个或一个以上的值(爱好1,爱好2,爱好3...)

     

    sex enum('male','female')

    hobby set('run','tennis','read','football')

    mysql> create table consumer(
        -> id int,
        -> name varchar(16),
        -> sex enum('male','female'),
        -> level enum('vip1','vip2','vip3'),
        -> hobby set('run','tennis','read','football')
        -> );
    Query OK, 0 rows affected (0.01 sec)

    插入一条记录

    mysql> insert into consumer values(1,'mike','male','vip1','run,read');
    Query OK, 1 row affected (0.00 sec)
    
    mysql> select * from consumer;
    +------+------+------+-------+----------+
    | id   | name | sex  | level | hobby    |
    +------+------+------+-------+----------+
    |    1 | mike | male | vip1  | run,read |
    +------+------+------+-------+----------+
    1 row in set (0.00 sec)

    插入一条记录时 在sex字段 插入一个不是 male或者female的字段 没有报错

    不在范围之内的 最后查询是空的

    mysql> insert into consumer values(2,'mike','ssadasd','vip2','tennis,football');
    Query OK, 1 row affected, 1 warning (0.00 sec)
    
    mysql> select * from consumer;
    +------+------+------+-------+-----------------+
    | id   | name | sex  | level | hobby           |
    +------+------+------+-------+-----------------+
    |    1 | mike | male | vip1  | run,read        |
    |    2 | mike |      | vip2  | tennis,football |
    +------+------+------+-------+-----------------+
    2 rows in set (0.00 sec)
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  • 原文地址:https://www.cnblogs.com/mingerlcm/p/9806258.html
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