mysql的 profiling不是默认打开的
查看profiling是否找开
mysql> show variables like "%pro%"; +---------------------------+-------+ | Variable_name | Value | +---------------------------+-------+ | profiling | OFF | | profiling_history_size | 15 | | protocol_version | 10 | | slave_compressed_protocol | OFF | +---------------------------+-------+
打开profiling
mysql> set profiling=1;
使用
mysql> show tables; +----------------+ | Tables_in_test | +----------------+ | test | | user | +----------------+ mysql> select * from test; mysql> show profiles; +----------+------------+------------------------+ | Query_ID | Duration | Query | +----------+------------+------------------------+ | 1 | 0.00054675 | show tables | | 2 | 0.00032400 | select * from test | +----------+------------+------------------------+ 2 rows in set (0.00 sec)
mysql> show profile for query 1; +----------------------+-----------+ | Status | Duration | +----------------------+-----------+ | (initialization) | 0.000028 | | checking permissions | 0.000007 | | Opening tables | 0.0000939 | | System lock | 0.0000017 | | Table lock | 0.0000055 | | init | 0.000009 | | optimizing | 0.0000027 | | statistics | 0.0000085 | | preparing | 0.0000065 | | executing | 0.000004 | | checking permissions | 0.000258 | | Sending data | 0.000049 | | end | 0.0000037 | | query end | 0.0000027 | | freeing items | 0.0000307 | | closing tables | 0.0000032 | | removing tmp table | 0.0000275 | | closing tables | 0.0000037 | | logging slow query | 0.000002 | +----------------------+-----------+ 19 rows in set (0.00 sec)