MySQL查看表占用空间大小

前言：在mysql中有一个默认的数据表information_schema，information_schema这张数据表保存了MySQL服务器所有数据库的信息。如数据库名，数据库的表，表栏的数据类型与访问权限等。再简单点，这台MySQL服务器上，到底有哪些数据库、各个数据库有哪些表，每张表的字段类型是什么，各个数据库要什么权限才能访问，等等信息都保存在information_schema表里面，所以请勿删改此表。

代码：

1，切换数据库

use information_schema;

2，查看数据库使用大小

select concat(round(sum(data_length/1024/1024),2),’MB’) as data from tables where table_schema=’DB_Name’ ;

3，查看表使用大小

select concat(round(sum(data_length/1024/1024),2),’MB’) as data from tables where table_schema=’DB_Name’ and table_name=’Table_Name’;

网上找的一个，亲测可用:

//先进去MySQL自带管理库：information_schema
//然后查询 data_length,index_length
//你自己的数据库名：dbname
//你自己的表名：tablename  

mysql> use information_schema;
Database changed
mysql> select data_length,index_length
    -> from tables where
    -> table_schema=‘dbname‘
    -> and table_name = ‘tablename‘;
+-------------+--------------+
| data_length | index_length |
+-------------+--------------+
|   166379520 |    235782144 |
+-------------+--------------+
row in set (0.02 sec)  

mysql> select concat(round(sum(data_length/1024/1024),2),‘MB‘) as data_length_MB,
    -> concat(round(sum(index_length/1024/1024),2),‘MB‘) as index_length_MB
    -> from tables where
    -> table_schema=‘dbname‘
    -> and table_name = ‘tablename‘;
+----------------+-----------------+
| data_length_MB | index_length_MB |
+----------------+-----------------+
| 158.67MB       | 224.86MB        |
+----------------+-----------------+
row in set (0.03 sec)

select concat(round(sum(data_length/1024/1024),2),‘MB‘) as data_length_MB, concat(round(sum(index_length/1024/1024),2),‘MB‘) as index_length_MB
from tables
where table_schema=‘passport‘ and table_name=‘tb_user_info‘;
-- 569.98MB 141.98MB

原文地址：https://www.cnblogs.com/shoshana-kong/p/11136919.html