MySQL turn on slow query log

SQL and Index optimization

database table Structure Optimization

System Configuration

Hardware

mysql> show variables like 'slow_query_log';+----------------+-------+| Variable_name  | Value |+----------------+-------+| slow_query_log | OFF   |+----------------+-------+1 row in set (0.00 sec)

Slow log query does not open, you can open a bit.

Find MY.CNF and add the following:sudo vim /usr/local/mysql/my.cnf

# 添加慢查询日志log_output=fileslow_query_log=on slow_query_log_file = /tmp/mysql-slow.loglong_query_time = 2

Restart MySQL.

mysql> show variables like 'slow_query_log';+----------------+-------+| Variable_name  | Value |+----------------+-------+| slow_query_log | ON    |+----------------+-------+1 row in set (0.00 sec)

At this time, the slow query log has been turned on.

$ sudo cat /tmp/mysql-slow.log /usr/local/mysql/bin/mysqld, Version: 5.6.40-log (Source distribution). started with:Tcp port: 3306  Unix socket: /tmp/mysql.sockTime                 Id Command    Argument

MySQL turn on slow query log