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  • 创建第一张表

    创建一个库

    create database 库名;
    

    切换

    use 库名;
    

    创建一个表的语法

    #语法:
    create table 表名(
    字段名1 类型[(宽度) 约束条件],
    字段名2 类型[(宽度) 约束条件],
    字段名3 类型[(宽度) 约束条件]
    );
    
    #注意:
    1. 在同一张表中,字段名是不能相同
    2. 宽度和约束条件可选
    3. 字段名和类型是必须的
    

    增加表中内容

    insert into 表名(键1,键2,键3) values #插入(值1,值2,值3);
    
    ps 注意插入值 字符串 形式
    

    实列

    创建一张表

    mysql> create database staff;#创建库
    Query OK, 1 row affected (0.00 sec)
    
    mysql> use staff; #切换库
    Database changed
    
    mysql> create table staff_info (#创建表
        id int,
        name varchar(50),
        age int(3),
        sex enum('male','female'),
        phone bigint(11),
        job varchar(11));
    Query OK, 0 rows affected (0.02 sec)
    
    
    mysql> show tables;#查看所有表
    +-----------------+
    | Tables_in_staff |
    +-----------------+
    | staff_info      |
    +-----------------+
    1 row in set (0.00 sec)
    
    mysql> desc staff_info;#查看表类型
    +-------+-----------------------+------+-----+---------+-------+
    | Field | Type                  | Null | Key | Default | Extra |
    +-------+-----------------------+------+-----+---------+-------+
    | id    | int(11)               | YES  |     | NULL    |       |
    | name  | varchar(50)           | YES  |     | NULL    |       |
    | age   | int(3)                | YES  |     | NULL    |       |
    | sex   | enum('male','female') | YES  |     | NULL    |       |
    | phone | bigint(11)            | YES  |     | NULL    |       |
    | job   | varchar(11)           | YES  |     | NULL    |       |
    +-------+-----------------------+------+-----+---------+-------+
    6 rows in set (0.00 sec)
    
    mysql> select id,name,sex from staff_info;#查询
    Empty set (0.00 sec)
    
    mysql> select * from staff_info;#查询
    Empty set (0.00 sec)
    
    
    mysql> insert into staff_info (id,name,age,sex,phone,job) values (1,'Alex',83,'female',13651054608,'IT');#插入
    Query OK, 1 row affected (0.00 sec)
    
    mysql> insert into staff_info values #插入(2,'Egon',26,'male',13304320533,'Teacher');
    Query OK, 1 row affected (0.00 sec)
    
    mysql> insert into staff_info values #插入(3,'nezha',25,'male',13332353222,'IT'),(4,'boss_jin',40,'male',13332353333,'IT');
    Query OK, 2 rows affected (0.00 sec)
    Records: 2  Duplicates: 0  Warnings: 0
    
    mysql> select * from staff_info;#查询
    +------+----------+------+--------+-------------+---------+
    | id   | name     | age  | sex    | phone       | job     |
    +------+----------+------+--------+-------------+---------+
    |    1 | Alex     |   83 | female | 13651054608 | IT      |
    |    2 | Egon     |   26 | male   | 13304320533 | Teacher |
    |    3 | nezha    |   25 | male   | 13332353222 | IT      |
    |    4 | boss_jin |   40 | male   | 13332353333 | IT      |
    +------+----------+------+--------+-------------+---------+
    4 rows in set (0.00 sec)
    
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  • 原文地址:https://www.cnblogs.com/saoqiang/p/12394148.html
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