六、MYSQL SQL语句

6.1 常用 SQL 命令（极速初体验）

1）登录

[root@hadoop102 ~]# mysql -h192.168.2.102 -P3306 -uroot -p'123456'

2）显示所有数据库

mysql> show databases;

3）进入指定的数据库

mysql> use mysql;

4）查看库中所有表

show tables from 库名，查看指库中的所有表

mysql> show tables;
mysql> show tables from mysql;

5）查看当前库

mysql> select database();

6）查看版本

• 进入 mysql 客户端之后

mysql> select version();

• 进入 mysql 客户端之前

[root@hadoop102 ~]# mysql --version
[root@hadoop102 ~]# mysql -V

7）新建一个新数据库

mysql> create database atguigu;

8）在库中，创建新表

• 选中数据库

mysql> use atguigu;

• 客户表

mysql> create table customer(id varchar(30),age int, name varchar(30),birthday date);

9）查看表结构

mysql> desc customer;

10）查看表数据

mysql> select * from customer;

11）查询特定列的表数据

mysql> select id, name, sex from student;

12）查询数据并进行过滤

mysql> select * from student where id > 3;

13）运算符查询

• and

mysql> select id, name, sex, age from student where age >=18 and age <=35;

• between and

mysql> select id, name, sex, age from student where age between 18 and 35;

14）查询变种

• or

mysql> select * from student where age=18 or age=35 or age=23;

• in

mysql> select * from student where age in (18,23,35);

• like %

% 匹配任意多个字符

mysql> select * from student where name like '%j%';

• like _

_ 只匹配一个字符

mysql> select * from student where name like '%_o%';

• is null

mysql> select * from student where email is null;

• is not null

mysql> select * from student where email is not null;

• order by asc 升序

mysql> select * from student order by age asc;

• order by desc 降序

15）插入数据

mysql> insert into student(id,name) values(1001, '小明');

温馨提示：插入 varchar 或 date 型的数据要用 单引号引起来

16）修改表

mysql> update student set name='小红' where id = 1001;

17）删除表记录

mysql> delete from student where id = 1001;

18）删除表

mysql> drop table customer;

19）删除数据库

mysql> drop database atguigu;

20）退出终端

温馨提示：这里总结了三种方式

• exit

mysql> exit;

• 终止

Ctrl + c

• quit

mysql> quit