Top answer doesn't work in mysql 5.6+. Use this instead:
[mysqld]
general_log = on
general_log_file=/usr/log/general.log
in your my.cnf / my.ini file
Ubuntu/Debian: /etc/mysql/my.cnf
Windows: c:\ProgramData\MySQL\MySQL Server 5.x
wamp: c:\wamp\bin\mysql\mysqlx.y.z\my.ini
xampp: c:\xampp\mysql\bin\my.ini.