Is there a way to make a dynamic world such as a MMORPG horizontally scalable? Imagine a open world of 500 players with data changing as fast as 20 updates player second. Last time I worked in a similar MMORPG, it used SQL, so obvioulsy it couldn't query the DB all the time. Instead, it loaded all players from the DB to memory as C objects and used them. That is, it scaled vertically. Would it be possible to make that server horizontally scalable instead? Is there a database designed to support that amount of updates concurrently?