To debug applications which use a mysql database, it comes in handy to enable the query log to get all SQL queries that were sent to the database. Open the MySQL configuration file (my.cnf)
vi /etc/mysql/my.cnf
and add the line:
log=/var/log/mysql.log
in the [mysql] section of the file. Depending on the Linux distribution that you use, the my.cnf file can be /etc/my.cnf or /etc/mysql/my.cnf.
Afterwards restart mysql to apply the new the configuration:
/etc/init.d/mysql restart
