数据库SQL语句 --- table(二)

关键词：alter,add,modify,change

1.查看当前数据库下所有表

show tables;

2.创建表

create table students(id int unsigned primary key auto_increment not null,name varchar(20) not null,age tinyint default 1,gender enum("男","女") default "男");

3.查看表结构

desc students;

4.添加一个字段名birthday(add)

alter table students add birthday datetime not null;

5.修改字段类型datetime to date(modify)

alter table students modify birthday date;

6.修改字段名和字段类型(change)

alter table students change birthday birth datetime not null;

7.删除字段birth

alter table students drop birth;

8.查看创建表

show create table students;

9.查看创建库

show create database python11;

10.删除表

drop table students;