MySQL 库大小、表大小、索引…

1、进去指定schema数据库（存放了其他的数据库的信息）
mysql> useinformation_schema;


2、查询所有数据的大小
mysql>select concat(round(sum(DATA_LENGTH/1024/1024),2),'MB') as datafrom TABLES;


3、查看指定数据库实例的大小，比如说数据库yoon
mysql>select concat(round(sum(DATA_LENGTH/1024/1024),2),'MB') as datafrom TABLES where table_schema='yoon';


4、查看指定数据库的表的大小，比如说数据库 yoon中的 yoon 表
mysql>select concat(round(sum(DATA_LENGTH/1024/1024),2),'MB') as datafrom TABLES
wheretable_schema='yoon' and table_name='yoon';


5、指定库的索引大小：


SELECTCONCAT(ROUND(SUM(index_length)/(1024*1024), 2), ' MB') AS 'TotalIndex Size' FROM TABLES WHERE table_schema = 'sakila';


6、指定库的指定表的索引大小：


SELECTCONCAT(ROUND(SUM(index_length)/(1024*1024), 2), ' MB') AS 'TotalIndex Size' FROM TABLES WHERE table_schema = 'test' andtable_name='sakila';


7、一个库中的使用情况：


SELECTCONCAT(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';