查询Mysql数据库所有数据库所占磁盘空间大小：

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 data_length desc;

查询某个数据库的所有表所占存储空间大小：只要加个where条件：where TABLE_SCHEMA = '数据库名称'

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 = 'jz-project'
group by TABLE_NAME
order by data_length desc;