make it possible to not use json with Postgres

[diwu1989]

using json field in postgres causes issues with aggregates and distinct because of missing equality checkers for the json columns.

there should be a way to opt-out of the postgres json column optimization

[diwu1989]

This should give a way out for folks who are having problem with #57

[diwu1989]

This may also solve #55

[bradjasper]

Hey @diwu1989 thanks for this. I'm actually in the process of removing PG json support entirely as it's caused nothing but problems. The next major release (with Django 1.7) will provide a breaking change here so this may not be needed anymore.

In the meantime you can use https://github.com/bradjasper/django-jsonfield/tree/postgresql if you're looking for something that will be supported.

[diwu1989]

aha! nice work, thank you very much.

Premature optimization is the root of all evils, die json column die.

[ravishivt]

@bradjasper Can you source what Django 1.7 will be doing differently in regards to this problem?

IMO, removing support for PG json field types is a step backwards. You lose the performance gains and the psql JSON querying API.