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  • MySQL 枚举集合

    ENUM

       枚举类型从众多选项中提取出一个选项,类似于单选的概念,最大可指定65535个选项。

       如果插入值不在其选项中,将会插入

    mysql> create table user(  # 创建用户表
        ->         name char(12),
        ->         gender enum("male","famale","outher"),  # 性别使用枚举类型再合适不过
        ->         age tinyint
        -> );
    Query OK, 0 rows affected (0.04 sec)
    
    mysql> insert into user(name,gender,age) values
        ->         ("Yunya","male",18),
        ->         ("Baby","famale",18);
    Query OK, 2 rows affected (0.00 sec)
    Records: 2  Duplicates: 0  Warnings: 0
    
    mysql> select * from user;
    +--------------+--------+------+
    | name         | gender | age  |
    +--------------+--------+------+
    | Yunya        | male   |   18 |
    | Baby         | famale |   18 |
    +--------------+--------+------+
    2 rows in set (0.00 sec)
    
    mysql>
    

    SET

       集合类型从众多选项中提取出多个选项,类似于多选的概念,最大可指定64个选项。

       如果插入值中有一个不在其选项中,该插入值将为,在其选项中的值将会正确插入。

    mysql> create table user(  # 创建用户表
        ->         name char(12),
        ->         gender enum("male","famale","outher"),
        ->         age tinyint,
        ->         hobby set("basketball","football","music","playgame") # 爱好使用集合类型再合适不过
        -> );
    Query OK, 0 rows affected (0.03 sec)
    
    mysql> insert into user(name,gender,age,hobby) values
        ->         ("Yunya","male",18,"basketball,playgame"),
        ->         ("Baby","famale",18,"football,music");  # 插入时按照 "选项1,选项2" 的方式进行插入
    Query OK, 2 rows affected (0.00 sec)
    Records: 2  Duplicates: 0  Warnings: 0
    
    mysql> select * from user;
    +--------------+--------+------+---------------------+
    | name         | gender | age  | hobby               |
    +--------------+--------+------+---------------------+
    | Yunya        | male   |   18 | basketball,playgame |
    | Baby         | famale |   18 | football,music      |
    +--------------+--------+------+---------------------+
    2 rows in set (0.00 sec)
    
    mysql>
    
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  • 原文地址:https://www.cnblogs.com/Yunya-Cnblogs/p/13585848.html
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