How good are Django 1.7 migrations at detecting things which have already happened? In particular, can you safely maintain South migrations alongside Django ones, or do you have to force users to switch?
The problem I envisage is that when you add 1.7 support to your app, you move your old migrations into south_migrations and start a clean migrations dir, as the instructions say - but what happens when your next release makes a database change? If you want to support all active versions (1.4, 1.6 and 1.7) you'd have to add a South migration and a 1.7 migration to support both groups of users - but then they no longer have a clean upgrade path from South to 1.7.
From reading the docs, it looks like 1.7 schema migrations may detect the changes have already been made and skip over them, but what will happen when you have data migrations too?
Does 1.7 figure out which operation you're up to by comparing your migrations to the database state, and starting migrations once the two match? What if at some point you return to an older set of model fields - does it match on the earliest or the latest?
I plan on avoiding the issue as long as possible: get my apps as feature complete as possible under South (with instructions for 1.7+ users for creating their own migrations), then bump the version when I switch from South to Django migrations. I'll then try to backport bugfixes to the South version (as long as they don't change the db) until support for Django 1.4 and 1.6 are dropped.
The problem I envisage is that when you add 1.7 support to your app, you move your old migrations into south_migrations and start a clean migrations dir, as the instructions say - but what happens when your next release makes a database change? If you want to support all active versions (1.4, 1.6 and 1.7) you'd have to add a South migration and a 1.7 migration to support both groups of users - but then they no longer have a clean upgrade path from South to 1.7.
From reading the docs, it looks like 1.7 schema migrations may detect the changes have already been made and skip over them, but what will happen when you have data migrations too?
Does 1.7 figure out which operation you're up to by comparing your migrations to the database state, and starting migrations once the two match? What if at some point you return to an older set of model fields - does it match on the earliest or the latest?
I plan on avoiding the issue as long as possible: get my apps as feature complete as possible under South (with instructions for 1.7+ users for creating their own migrations), then bump the version when I switch from South to Django migrations. I'll then try to backport bugfixes to the South version (as long as they don't change the db) until support for Django 1.4 and 1.6 are dropped.