DatabaseError: value too long for type character varying(100)

I can bet money you have a models.SlugField without length set. The default length is 50 characters, most likely it's not enough for your use case.

Change it to models.SlugField(max_length=255) and migrate your database schema.

I also had this problem when using a filefield and was scratching my head for a while. Of course the default FileField instances are created with a 100 character limit.

https://docs.djangoproject.com/en/dev/ref/models/fields/#filefield

This is an error message from Postgres and not django.

You seem to have changed the length of the field in the models.py, but that doesn't change the database length which was created when you did a manage.py syncdb.

You have to alter the length of the field in the database, directly.