查看MySQL语法详细执行时间与CPU/內存使用量：MySQL Query Profiler
MySQL的SQL语法调整主要都是使用EXPLAIN，但是这个并没办法知道详细的Ram（Memory）/CPU等使用量.文章源自很文博客https://www.hinven.com很文博客-https://www.hinven.com/50762.html
于MySQL 5.0.37以上开始支持MySQL Query Profiler，可以查询到此SQL会执行多少时间，并看出CPU/Memory使用量，执行过程中System lock，Table lock花多少时间等等.文章源自很文博客https://www.hinven.com很文博客-https://www.hinven.com/50762.html
MySQL Query Profile详细介绍可见：Using the New MySQL Query Profiler（2007.04.05发表）文章源自很文博客https://www.hinven.com很文博客-https://www.hinven.com/50762.html
性能分析主要分下述三种（转载自上篇）：文章源自很文博客https://www.hinven.com很文博客-https://www.hinven.com/50762.html
Bottleneck analysis - focuses on answering the questions: What is my database server waiting on；what is a user connection waiting on；what is a piece of SQL code waiting on？文章源自很文博客https://www.hinven.com很文博客-https://www.hinven.com/50762.html
Workload analysis - examines the server and who is logged on to determine the resource usage and activity of each.文章源自很文博客https://www.hinven.com很文博客-https://www.hinven.com/50762.html
Ratio-based analysis - utilizes a number of rule-of-thumb ratios to gauge performance of a database，user connection，or piece of code.文章源自很文博客https://www.hinven.com很文博客-https://www.hinven.com/50762.html
MySQL Query Profile使用方法
启动
mysql> set profiling=1；#此命令于MySQL会于information_schema的database建立一个PROFILING的table来纪录.
SQL profiles show
mysql> show profiles；#从启动之后所有语法及使用时间，含错误语法都会纪录.
ex:（root@localhost）[test]> show profiles；#注意Query_ID，下面执行时间统计等，都是依Query_ID在纪录
+----------+------------+---------------------------+
| Query_ID | Duration | Query |
+----------+------------+---------------------------+
| 1 | 0.00090400 | show profile for query 1 |
| 2 | 0.00008700 | select * from users |
| 3 | 0.00183800 | show tables |
| 4 | 0.00027600 | mysql> show profiles |
+----------+------------+---------------------------+
查询所有花费时间加总
mysql> select sum（duration）from information_schema.profiling where query_id=1；#Query ID = 1
+---------------+
| sum（duration）|
+---------------+
| 0.000447 |
+---------------+
查询各执行阶段花费多少时间
mysql> show profile for query 1；#Query ID = 1
+--------------------+------------+
| Status | Duration |
+--------------------+------------+
|（initialization）| 0.00006300 |
| Opening tables | 0.00001400 |
| System lock | 0.00000600 |
| Table lock | 0.00001000 |
| init | 0.00002200 |
| optimizing | 0.00001100 |
| statistics | 0.00009300 |
| preparing | 0.00001700 |
| executing | 0.00000700 |
| Sending data | 0.00016800 |
| end | 0.00000700 |
| query end | 0.00000500 |
| freeing items | 0.00001200 |
| closing tables | 0.00000800 |
| logging slow query | 0.00000400 |
+--------------------+------------+
查询各执行阶段花费的各种资源列表
mysql> show profile cpu for query 1；#Query ID = 1
+--------------------------------+----------+----------+------------+
| Status | Duration | CPU_user | CPU_system |
+--------------------------------+----------+----------+------------+
|（initialization）| 0.000007 | 0 | 0 |
| checking query cache for query | 0.000071 | 0 | 0 |
| Opening tables | 0.000024 | 0 | 0 |
| System lock | 0.000014 | 0 | 0 |
| Table lock | 0.000055 | 0.001 | 0 |
| init | 0.000036 | 0 | 0 |
| optimizing | 0.000013 | 0 | 0 |
| statistics | 0.000021 | 0 | 0 |
| preparing | 0.00002 | 0 | 0 |
| executing | 0.00001 | 0 | 0 |
| Sending data | 0.015072 | 0.011998 | 0 |
| end | 0.000021 | 0 | 0 |
| query end | 0.000011 | 0 | 0 |
| storing result in query cache | 0.00001 | 0 | 0 |
| freeing items | 0.000018 | 0 | 0 |
| closing tables | 0.000019 | 0 | 0 |
| logging slow query | 0.000009 | 0 | 0 |
+--------------------------------+----------+----------+------------+
mysql> show profile IPC for query 1；
+--------------------------------+----------+---------------+-------------------+
| Status | Duration | Messages_sent | Messages_received |
+--------------------------------+----------+---------------+-------------------+
|（initialization）| 0.000007 | 0 | 0 |
| checking query cache for query | 0.000071 | 0 | 0 |
| Opening tables | 0.000024 | 0 | 0 |
| System lock | 0.000014 | 0 | 0 |
| Table lock | 0.000055 | 0 | 0 |
| init | 0.000036 | 0 | 0 |
| optimizing | 0.000013 | 0 | 0 |
| statistics | 0.000021 | 0 | 0 |
| preparing | 0.00002 | 0 | 0 |
| executing | 0.00001 | 0 | 0 |
| Sending data | 0.015072 | 0 | 0 |
| end | 0.000021 | 0 | 0 |
| query end | 0.000011 | 0 | 0 |
| storing result in query cache | 0.00001 | 0 | 0 |
| freeing items | 0.000018 | 0 | 0 |
| closing tables | 0.000019 | 0 | 0 |
| logging slow query | 0.000009 | 0 | 0 |
+--------------------------------+----------+---------------+-------------------+
其它属性列表
ALL - displays all information
BLOCK IO - displays counts for block input and output operations
CONTEXT SWITCHES - displays counts for voluntary and involuntary context switches
IPC - displays counts for messages sent and received
MEMORY - is not currently implemented
PAGE FAULTS - displays counts for major and minor page faults
SOURCE - displays the names of functions from the source code，together with the name and line number of the file in which the function occurs
SWAPS - displays swap counts
设定Profiling存的Size
mysql> show variables where variable_name='profiling_history_size'；#预设是15笔
关闭
mysql> set profiling=0；
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