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  • 重拾SQL——从无到有

    2016.10.22

    因为工作需要,在这里提前重拾sql。

    0.创建并选择数据库

    mysql> SHOW DATABASES;
    
    +--------------------+
    | Database           |
    +--------------------+
    | information_schema |
    | menagerie          |
    | mysql              |
    | performance_schema |
    | phpmyadmin         |
    | test               |
    +--------------------+
    6 rows in set (0.00 sec)
    

    1.创建并选择数据库

    mysql> CREATE DATABASE tianyuan;
    
    Query OK, 1 row affected (0.00 sec)
    

    2.查看创建后的数据库

    mysql> SHOW DATABASES;
    
    +--------------------+
    | Database           |
    +--------------------+
    | information_schema |
    | menagerie          |
    | mysql              |
    | performance_schema |
    | phpmyadmin         |
    | test               |
    | tianyuan           |
    +--------------------+
    7 rows in set (0.00 sec)
    

    3.访问它

    mysql> USE tianyuan
    
    Database changed
    

    4.指定数据库中表的布局

    mysql> CREATE TABLE pet (name VARCHAR(20), owner VARCHAR(20),
    	-> species VARCHAR(20), sex CHAR(1), birth DATE, death DATE);
    
    Query OK, 0 rows affected (0.14 sec)
    

    5.显示表格

    mysql> SHOW TABLES;
    
    +--------------------+
    | Tables_in_tianyuan |
    +--------------------+
    | pet                |
    +--------------------+
    1 row in set (0.00 sec)
    

    6.验证表是按期望的方式创建(如果你忘记表中的列的名称或类型时)

    mysql> DESCRIBE pet;
    
    +---------+-------------+------+-----+---------+-------+
    | Field   | Type        | Null | Key | Default | Extra |
    +---------+-------------+------+-----+---------+-------+
    | name    | varchar(20) | YES  |     | NULL    |       |
    | owner   | varchar(20) | YES  |     | NULL    |       |
    | species | varchar(20) | YES  |     | NULL    |       |
    | sex     | char(1)     | YES  |     | NULL    |       |
    | birth   | date        | YES  |     | NULL    |       |
    | death   | date        | YES  |     | NULL    |       |
    +---------+-------------+------+-----+---------+-------+
    6 rows in set (0.01 sec)
    

    7.选择表格所有列的内容(无内容时)

    mysql> SELECT * FROM pet;
    
    Empty set (0.00 sec)
    

    8.将数据装入表中

    • LOAD DATA

      mysql> LOAD DATA LOCAL INFILE '/Users/v/Desktop/1.txt' INTO TABLE pet;
      

      '/Users/v/Desktop/1.txt':

        Fluffy	Harold	cat	f	1993-02-04
        Claws	Gwen	cat	m	1994-03-17
        Buffy	Harold	dog	f	1989-05-13
        

      加载后

        Query OK, 3 rows affected, 3 warnings (0.07 sec)     
        Records: 3  Deleted: 0  Skipped: 0  Warnings: 3
        

      查看

      mysql> SELECT * FROM pet;
      
        +--------+--------+---------+------+------------+-------+
        | name   | owner  | species | sex  | birth      | death |
        +--------+--------+---------+------+------------+-------+
        | Fluffy | Harold | cat     | f    | 1993-02-04 | NULL  |
        | Claws  | Gwen   | cat     | m    | 1994-03-17 | NULL  |
        | Buffy  | Harold | dog     | f    | 1989-05-13 | NULL  |
        +--------+--------+---------+------+------------+-------+
        3 rows in set (0.00 sec)
        
    • INSERT

       mysql> INSERT INTO pet 
       	-> VALUES ('Puffball','Diane','hamster','f','1999-03-30',NULL);
      
        Query OK, 1 row affected (0.05 sec)
        

      查看

      mysql> SELECT * FROM pet;
      
        +----------+--------+---------+------+------------+-------+
        | name     | owner  | species | sex  | birth      | death |
        +----------+--------+---------+------+------------+-------+
        | Fluffy   | Harold | cat     | f    | 1993-02-04 | NULL  |
        | Claws    | Gwen   | cat     | m    | 1994-03-17 | NULL  |
        | Buffy    | Harold | dog     | f    | 1989-05-13 | NULL  |
        | Puffball | Diane  | hamster | f    | 1999-03-30 | NULL  |
        +----------+--------+---------+------+------------+-------+
        4 rows in set (0.00 sec)
        

    9.删除数据库

    mysql> SHOW DATABASES;
    
    +--------------------+
    | Database           |
    +--------------------+
    | information_schema |
    | menagerie          |
    | mysql              |
    | performance_schema |
    | phpmyadmin         |
    | test               |
    | tianyuan           |
    +--------------------+
    7 rows in set (0.00 sec)
    

    删除

    mysql> DROP DATABASE test;
    
    Query OK, 0 rows affected (0.02 sec)
    

    查看删除效果

    mysql> SHOW DATABASES;
    
    +--------------------+
    | Database           |
    +--------------------+
    | information_schema |
    | menagerie          |
    | mysql              |
    | performance_schema |
    | phpmyadmin         |
    | tianyuan           |
    +--------------------+
    6 rows in set (0.00 sec)
    
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  • 原文地址:https://www.cnblogs.com/thqy39/p/5989079.html
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