1.mysql -uroot -p 123456

2.show databases; 查看全部数据库

3.select database(); 查看当前数据库

4.show variables like 'port';

5. 查看当前数据库大小，如查看springdata库大小

select concat(round(sum(data_length)/(1024*1024),2) + round(sum(index_length)/(1024*1024),2),'MB') as 'DB Size'

-> from tables

-> where table_schema='springdata';

6. 查看数据所占有的空间

select concat(round(sum(data_length)/(1024*1024),2),'MB') as 'DB Size'

-> from tables

-> where table_schema='springdata';

7.查看索引所占用的空间

select concat(round(sum(index_length)/(1024*1024),2),'MB') as 'DB Size'

-> from tables

-> where table_schema='INVOICE';

8.查看数据库编码

 show variables like 'character%';

9.status

10.show tables;

11. 查看权限

　　show grants for 'root'@'localhost';

12.某个人的权限

show grants for 'root'@'localhost';