1、查詢整個mysql資料庫，整個庫的大小；單位轉換為MB。select concat(round(sum(DATA_LENGTH/1024/1024),2),"MB") as data from information_schema.TABLES2、查詢mysql資料庫，某個庫的大小；select concat(round(sum(DATA_LENGTH/1024/1024),2),"MB") as data from information_schema.TABLES where table_schema = "testdb"select concat(round(sum(DATA_LENGTH/1024/1024),2),"MB") as data from information_schema.TABLES where table_schema = "testdb" and table_name = "test_a";select concat(round(sum(DATA_LENGTH/1024/1024),2),"MB") as data from information_schema.TABLES where table_schema = "testdb" and table_name like "test%";