MySQL 庫大小、表大小、索引大小查詢命令

1、進去指定schema 數據庫（存放了其他的數據庫的信息）
     mysql> use information_schema;


2、查詢所有數據的大小 
     mysql> select concat(round(sum(DATA_LENGTH/1024/1024),2),'MB') as data from TABLES;


3、查看指定數據庫實例的大小，比如說數據庫 yoon 
     mysql> select concat(round(sum(DATA_LENGTH/1024/1024),2),'MB') as data from TABLES where table_schema='yoon';


4、查看指定數據庫的表的大小，比如說數據庫 yoon 中的 yoon 表 
     mysql> select concat(round(sum(DATA_LENGTH/1024/1024),2),'MB') as data from TABLES 
                 where table_schema='yoon' and table_name='yoon';


5、指定庫的索引大小：


SELECT CONCAT(ROUND(SUM(index_length)/(1024*1024), 2), ' MB') AS 'Total Index Size' FROM TABLES  WHERE table_schema = 'sakila'; 


6、指定庫的指定表的索引大小：


SELECT CONCAT(ROUND(SUM(index_length)/(1024*1024), 2), ' MB') AS 'Total Index Size' FROM TABLES  WHERE table_schema = 'test' and table_name='sakila'; 


7、一個庫中的使用情況：


SELECT CONCAT(table_schema,'.',table_name) AS 'Table Name', CONCAT(ROUND(table_rows/1000000,4),'M') AS 'Number of Rows', CONCAT(ROUND(data_length/(1024*1024*1024),4),'G') AS 'Data Size', CONCAT(ROUND(index_length/(1024*1024*1024),4),'G') AS 'Index Size', CONCAT(ROUND((data_length+index_length)/(1024*1024*1024),4),'G') AS'Total'FROM information_schema.TABLES WHERE table_schema LIKE 'sakila';