[scriptkiddy]

> There is a perception amongst lower programmers that FKs are only a thing you enable in production, that they are an impediment to rapid iteration.

Really? I've been working as a web programmer for about 5 years now. I use the term Web Programmer because I feel like the term Web Developer carries with it the connotation that you only work with Javascript.

My specialty is definitely with Python and more specifically with Django. Django's ORM is the first ORM I ever used. Maybe it's because I self taught, but I never had the inclination that FKs were an impediment to rapid iteration. In fact, quite the opposite. FKs are a fantastic way to enforce relationship constraints between tables/objects/models/whatever you want to call them.

Whenever I start on a new project, the first thing I do is start defining my data structure. In Django, this mostly involves using the ORM layer to define Model Classes. I usually define the core sets of models necessary for the application. As an example, if I were building a simple blog, I'd start by overriding Django's built in user model so I have the flexibility to add columns or place constraints on existing columns. Then I would define the post model which includes an `author` and a `category` FK column. Then I would define the `Category` model. I generate a migration script and run it. Every time I need to make a change to the Schema, I simply add or change whatever I need to and generate a new migration script alongside the old one. These migrations are dependent upon previous migrations and have version numbers. If I need to, I can roll back to a previous schema. Django makes this all very simple and actually separates the migrations out by which app the model definitions reside in. This means that I can make changes to multiple model definitions and only apply the changes to the Db for one of those model classes. It's very flexible.

So, after my long-winded explanation above, I don't see how people could find FKs to be restrictive when there are so many tools like Django's ORM and migration system that makes altering your schema so simple.