I have done this quite a few times in the past, but not recently. I was given three days to convert an existing postgres database (front ended with Zope) to Django 1.3. I thought it would be useful to document what I did here for my own future reference and to record any gotchas for posterity. The database I am converting is nine years old, so plenty of cruft through the years, although the basic structure is sound.
Note that the website of this application is not particularly complicated. Most of the core work of this application is done via backend processes written with Twisted. The front end is used for displaying the system status and allowing for data to be modified, with a few additional complications. The system will work without any web front end (although this is hardly ideal) without stopping production, so the risk is minimised.
This is the first day – although I only started from the beginning of the afternoon, so it’s the first half a day.