Unique model field in Django and case sensitivity (postgres)

Question

Consider the following situation: -

Suppose my app allows users to create the states / provinces in their country. Just for clarity, we are considering only ASCII ch

Answer 1

You could define a custom model field derived from models.CharField. This field could check for duplicate values, ignoring the case.

Custom fields documentation is here http://docs.djangoproject.com/en/dev/howto/custom-model-fields/

Look at http://code.djangoproject.com/browser/django/trunk/django/db/models/fields/files.py for an example of how to create a custom field by subclassing an existing field.

You could use the citext module of PostgreSQL https://www.postgresql.org/docs/current/static/citext.html

If you use this module, the the custom field could define "db_type" as CITEXT for PostgreSQL databases.

This would lead to case insensitive comparison for unique values in the custom field.