mysql - 如何确定特定 MySQL 表占用了多少磁盘空间？

Question

有没有一种快速的方法来确定一个特定的 MySQL 表占用了多少磁盘空间？该表可能是 MyISAM 或 Innodb。

Answer 1

对于一个表 mydb.mytable 运行这个:

字节

SELECT (data_length+index_length) tablesize
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';

千字节

SELECT (data_length+index_length)/power(1024,1) tablesize_kb
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';

兆字节

SELECT (data_length+index_length)/power(1024,2) tablesize_mb
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';

技嘉

SELECT (data_length+index_length)/power(1024,3) tablesize_gb
FROM information_schema.tables
WHERE table_schema='mydb' and table_name='mytable';

通用

这是一个通用查询，其中最大单位显示为 TB (TeraBytes)

SELECT 
    CONCAT(FORMAT(DAT/POWER(1024,pw1),2),' ',SUBSTR(units,pw1*2+1,2)) DATSIZE,
    CONCAT(FORMAT(NDX/POWER(1024,pw2),2),' ',SUBSTR(units,pw2*2+1,2)) NDXSIZE,
    CONCAT(FORMAT(TBL/POWER(1024,pw3),2),' ',SUBSTR(units,pw3*2+1,2)) TBLSIZE
FROM
(
    SELECT DAT,NDX,TBL,IF(px>4,4,px) pw1,IF(py>4,4,py) pw2,IF(pz>4,4,pz) pw3
    FROM 
    (
        SELECT data_length DAT,index_length NDX,data_length+index_length TBL,
        FLOOR(LOG(IF(data_length=0,1,data_length))/LOG(1024)) px,
        FLOOR(LOG(IF(index_length=0,1,index_length))/LOG(1024)) py,
        FLOOR(LOG(IF(data_length+index_length=0,1,data_length+index_length))/LOG(1024)) pz
        FROM information_schema.tables
        WHERE table_schema='mydb'
        AND table_name='mytable'
    ) AA
) A,(SELECT 'B KBMBGBTB' units) B;

试试看!!!