Based on what the OP says he wants to build, I'd say things like joins, the out of the box many-to-many functionality, etc. Basically, how do you link your mode

Based on what the OP says he wants to build, I'd say things like joins, the out of the box many-to-many functionality, etc. Basically, how do you link your models together in a sane way. No need for ORM replacement. Just good SQL fundamental knowledge. http://sql.learncodethehardway.org/book/ http://sql.learncodethehardway.org/book/ would be a good start.