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  • 8.3.5

    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...)

    create table consumer(
     id int,
     name char(16), 
     sex enum('male','female'),
     level enum ('vip1','vip2','vip3'),
     hobbies set('play','music','run')
    );
    
    insert into consumer values
    (1,'cmz','male','vip1','music,run');
    
    # 因为不在选择范围内会报错
    insert into consumer values
    (2,'cmz','xxx','vip1','music,run'); 
    # 操作过程
    mysql> create table consumer(
        ->  id int,
        ->  name char(16), 
        ->  sex enum('male','female'),
        ->  level enum ('vip1','vip2','vip3'),
        ->  hobbies set('play','music','run')
        -> );
    Query OK, 0 rows affected (0.03 sec)
    
    mysql> insert into consumer values
        -> (1,'cmz','male','vip1','music,run');
    Query OK, 1 row affected (0.04 sec)
    mysql> select * from consumer;
    +------+------+------+-------+-----------+
    | id   | name | sex  | level | hobbies   |
    +------+------+------+-------+-----------+
    |    1 | cmz  | male | vip1  | music,run |
    +------+------+------+-------+-----------+
    1 row in set (0.00 sec)
    
    mysql> insert into consumer values
        -> (1,'cmz','xxx','vip1','music,run');
    ERROR 1265 (01000): Data truncated for column 'sex' at row 1
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  • 原文地址:https://www.cnblogs.com/caimengzhi/p/8552508.html
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