I started playing World of Warcraft at the same time I was studying database systems at university and had a similar curiosity. Twenty years later the AzerothCore project pretty much satisfies this curiosity, they've done an incredible job reverse engineering the game server and its database.
That’s fascinating. I didn’t realize the WoW server was so database heavy. do you know if the original game logic was implemented mostly in stored procedures, or was it just used for persistence and the engine handled the rules elsewhere?