"I would imagine (but have no pratical experience/knowledge) that a game server most likely handles a lot of the operations/changes that need done in-memory and has some kind of background thread which will periodically save changes to the database. That way it would be able to service all the clients quickly without waiting on the database."
This is what Kicken said about updating and stuff via the client for a MMO.
In other words
I use a "Attackmob" function each time a user clicks "attack" to swing their sword or hit a monster. This function queries 3 queries and spits out data via AJAX and appends it to the page. [Monster loss of life/etc] So it seems like it's dynamic gameplay.
Edited by Monkuar, 13 September 2013 - 11:07 PM.