MySQL数据和索引占用空间查询

链接地址
对原文代码进行了修改，如下：

关于查数据库和表中的数据和索引所占空间的大小的SQL方法：
查询information_schema架构中的tables表。
代码：
查询所有数据库占用磁盘空间大小的SQL语句：

select table_schema,concat(truncate(sum(data_length)/1024/1024,2),"MB") as data_size,
concat(truncate(sum(index_length)/1024/1024,2),"MB") as index_size
from information_schema.tables
group by table_schema
order by sum(data_length) desc;

查询单个库中所有表磁盘占用大小的SQL语句：

select table_name,concat(truncate(data_length/1024/1024,2),"MB") as data_size,
concat(truncate(index_length/1024/1024,2),"MB") as index_size
from information_schema.tables where table_schema="employees"
order by data_length desc;