mysql 库和表占用空间查询

1. 查看该数据库实例下所有库大小，得到的结果是以MB为单位

select table_schema,sum(data_length)/1024/1024 as data_length,sum(index_length)/1024/1024
as index_length,sum(data_length+index_length)/1024/1024 as sum from information_schema.tables;

2、查看该实例下各个库大小

select table_schema, sum(data_length+index_length)/1024/1024 as total_mb,
sum(data_length)/1024/1024 as data_mb, sum(index_length)/1024/1024 as index_mb,
count(*) as tables, curdate() as today from information_schema.tables group by table_schema order by 2 desc;

3、查看单个库的大小

select concat(truncate(sum(data_length)/1024/1024,2),'mb') as data_size,
concat(truncate(sum(max_data_length)/1024/1024,2),'mb') as max_data_size,
concat(truncate(sum(data_free)/1024/1024,2),'mb') as data_free,
concat(truncate(sum(index_length)/1024/1024,2),'mb') as index_size
from information_schema.tables where table_schema = 'jwtnew2017';

4、查看单个表的状态

show table status from jwtnew2017 where name = 't_user'

5、查看单库下所有表的状态

use infomation_schema;
select table_name, (data_length/1024/1024) as data_mb , (index_length/1024/1024) 
as index_mb, ((data_length+index_length)/1024/1024) as all_mb, table_rows
from tables where table_schema = 'mydb'