Enable query log without restarting mysql on Linux

Steps to enable mysql query log on mysql server without restarting mysql process on Ubuntu and other Linux flavours.

1. Set general_log_file on SQL prompt:

   SET GLOBAL general_log_file = '/var/log/mysql/query.log';
   

2. set general_log to value ‘ON’

   SET GLOBAL general_log = 'ON';
   

3. Check query log. You may have to use sudo in case you dont have read access to log file.

   $ tail -f /var/log/mysql/query.log
   

4. In case you want to disable query log

   SET GLOBAL general_log = 'OFF';
   

Note that this approach is not mysql restart safe. To permanently enable query log, please visit Mysql – how to enable query log.