SELECT ROUND(SUM(data_length+index_length)/1024/1024)AS total_mb, ROUND(SUM(data_length)/1024/1024)AS data_mb, ROUND(SUM(index_length)/1024/1024)AS index_mb FROM INFORMATION_SCHEMA.TABLES;
确定当前数据和索引的总大小
原文：http://www.cnblogs.com/xiaoit/p/4464338.html
