How To Enable Slow Query In MySQL
If you know how to enable slow query in MySQL it’s easy to setup. It can help you analyze the database server response time. you can enable and check a slow query log when you configure with a single command in MySQL.
By default, slow_query_log is off in MySQL 5.5. This helps you to find out which query is taking a long time to execute than the given threshold.
There are two ways of checking slow_query_log is enabled or not.
Method 1 : show variables like “slow_query_log”;
Method 2 : mysqladmin var |grep log_slow_queries
As you can see slow_query_log is off So let’s enable it by globally thorough command in MySQL if you want to enable it permanent you will have to put this in my.cnf file.
SET GLOBAL slow_query_log = 1;
SET GLOBAL slow_query_log = 0;
You need to Set slow log query file path
SET GLOBAL slow_query_log_file = ‘/var/log/mariadb/my-slow.log’;
Now Check slow query will be ON
Add permanent in vim /etc/my.cnf
As you can see, By Default slow query log file is located at /var/lib/mysql/mysql-slow.log
Now restart the service,
You’re done check slow query log configure slow query log check slow query log enable slow query log