High performance MySQL (2) Single SQL performance

In practical applications, there are 3 ways to analyze a single query SQL performance: Show status, show profiles, and slow query logs.

First, use show profile

1, the default is disabled, open in the session

#开启profile
Set profiling=1;

2. When a query arrives at the server, the tool logs the profiling information to a temporary table and gives the query an integer identifier starting at 1, which can be viewed through show profiles.

3, the above only shows the accuracy of time, but sometimes we need more information then we can use

Show profiles for query 1; see specific information

See more highlights of this column: http://www.bianceng.cnhttp://www.bianceng.cn/database/MySQL/