mysql常用DDL命令

DDL主要负责数据库的创/改/查/删以及表格的创/改/查/删

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1.创建数据库:

create database [数据库名] character set [字符编码];

例如:

create database study1 character set utf8; 

2.查看数据库:

show databases;

3.查看数据库创建明细:

show create database [数据库名字]; 

4.修改数据库编码:

alter database [数据库名] character set [字符编码];

5.删除数据库:

drop database [数据库名];

6.使用数据库:

use [数据库名];

7.创建表格:

create table employee(id int,name varchar(20),sex char(2),birthday date,job varchar(50),salary double(7,2));

8.查看表的结构:

desc [表名];

9.在表中插入列:

alter table employee add address varchar(100);

10.修改列字符的属性:

ALTER TABLE employee MODIFY job VARCHAR(20);

注:即将原来varchar(50)改为20;

11.删除某列:

ALTER TABLE employee DROP address;

12.更改表名:

RENAME TABLE employee to user;

13.查看表的创建细节:

SHOW CREATE TABLE user;

14.修改字段名:

ALTER TABLE user CHANGE name username VARCHAR(10);

15.删除表:

DROP TABLE user;