use information_schema; select concat(round(sum(index_LENGTH)/(1024*1024),2),'MB') as 'Index Size(MB)', index_LENGTH as 'Index Size(Bytes)' from tables where table_schema='my_db' and table_name='table_name';
重建索引(MyISAM下面语句有效;innodb下面语句无效,需要先删除索引,然后重建):
use my_db; REPAIR TABLE table_name QUICK;