mysql尋找sql耗時瓶頸 show profiles

標籤：

1、首先查看是否開啟profiling功能

SHOW VARIABLES LIKE ‘%pro%‘; 

或者

SELECT @@profiling; 

2、開啟profiling

SET profiling=1; 

3、執行sql語句
例如：

SELECT     table_schema AS ‘Db Name‘,    ROUND( SUM( data_length + index_length ) / 1024 / 1024, 3 ) AS ‘Db Size (MB)‘,    ROUND( SUM( data_free ) / 1024 / 1024, 3 ) AS ‘Free Space (MB)‘  FROM information_schema.tables  GROUP BY table_schema ;  

4、查看結果

SHOW profiles;  SHOW profile ALL FOR QUERY 94;  94是查詢ID號。SHOW profiles文法：SHOW PROFILE [type [, type] … ]      [FOR QUERY n]      [LIMIT row_count [OFFSET offset]]  type:      ALL    | BLOCK IO    | CONTEXT SWITCHES    | CPU    | IPC    | MEMORY    | PAGE FAULTS    | SOURCE    | SWAPS  

 本文轉自http://blog.csdn.net/k_scott/article/details/8804384

mysql尋找sql耗時瓶頸 show profiles