Object Relational Mappers (ORMs) are awesome enhancers of developer productivity. The freedom of having the library write that SQL and give you back a useful, rich model instance (or a bunch of them) instead of just a tuple or a list of records is simply amazing. But if you forget you have an actual database behind all that convenience, then it’ll bite you back, usually when you’ve been in production for a while, after you’ve accumulated enough data that your once speedy …