Home Database Mysql Tutorial 不得不知道的mysql的基本操作

不得不知道的mysql的基本操作

Jun 07, 2016 pm 03:27 PM
mysql Basic Basic operations statement

MYSQL的基本语句 1.Createdatabase 数据库名; 创建数据库类型 2.show database; 显示所有数据库信息 3.use 数据库名; 选择数据库 4.drop database 数据库名; 删除数据库 5.create table 表名 (字段名1 类型, 字段名2 类型) 创建表 6.show cloums from

MYSQL的基本语句

1.Create database 数据库名;

创建数据库类型

 

2.show database;

显示所有数据库信息

 

3.use 数据库名;

选择数据库

 

4.drop database 数据库名;

删除数据库

 

5.create table 表名 (字段名1 类型, 字段名2 类型)

创建表格

 

6.show cloums from 数据库名.数据表名

显示指定的表结构

 

7.desc 表名列名;

显示表中一个字段的结构

 

8.alter table 表名 操作的关键字 具体操作

修改表

 

9.rename table 旧表名 to 新表名

改表名字

 

10.Drop table 表名;

删除表的名字

 

11.insert into 表名(字段名1,字段名2) values (对应的值1,对应的值2);

插入表

 

12.Concat()联合多列

使用concat函数可以联合多个字段,构成一个总的字符串

 

Select concat(name ,“:”,age) from user;

 

13.limit限定查询行数

Select * from 表名 limit 2,3

意思是从第二条记录连续读3条

 

14.sum()求和

15.Update 表名 set  字段名=对应的值 where 条件

更新表

16. delete from 表名 where 条件

删除表中的记录

17.

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