Polymorphic Associations

It’s been at least a week since something in Rails made me stop and think “whoa – cool!” but today it was polymorphic associations. I am impressed indeed.

Good examples of how to implement are a bit hard to come by though. Polymorphic Association in Rails by Manik was the clearest for me, particularly his simple demonstration in the console.

Intuitively this feels like a feature that it might be easy to abuse. Has anyone done any performance benchmarking on how linking relationships like this might impact an application?