Mysql查询数据量大小

--按实例
SELECT CONCAT(round(sum(DATA_LENGTH/1024/1024/1024),2),"GB") as datazise FROM information_schema.TABLES
--按库
SELECT table_schema,CONCAT(round(sum(DATA_LENGTH/1024/1024/1024),2),"GB") as datazise FROM information_schema.TABLES GROUP BY table_schema;
--按表
SELECT table_schema,table_name,CONCAT(round(sum(DATA_LENGTH/1024/1024),2),"MB") as datazise FROM information_schema.TABLES GROUP BY table_schema,table_name;