MySQL索引的維護與最佳化——尋找重複及冗餘索引

標籤：select   使用方法   weight   使用   seq   rom   sele   dup   index   

方法一：通過MySQL的information_schema資料庫 尋找重複與冗餘索引

SELECT a.table_schema AS ‘資料庫‘, a.table_name AS ‘表名‘, a.index_name AS ‘索引1‘, b.index_name AS ‘索引2‘, a.column_name AS ‘重複列名‘FROM information_schema.statistics a    JOIN statistics b ON a.table_schema = b.table_schema        AND a.table_name = b.table_name        AND a.seq_in_index = b.seq_in_index        AND a.column_name = b.column_nameWHERE a.seq_in_index = 1    AND a.index_name != b.index_name

 方法二：通過工具

用pt-duplicate-key-checker 工具檢查重複及冗餘索引使用方法 pt-duplicate-key-checker -hxxx -uxxx -pxxx

 

尋找重複與冗餘索引

 

參考慕課網：http://www.imooc.com/video/3998

MySQL索引的維護與最佳化——尋找重複及冗餘索引