Irrational Exuberance

You are writing a comment about How to Migrate Data Across Model Changes, here is a quick summary:

If you've built a large program in Django (or, ya know, anything that uses a database), you know about migrating data. Specifically, you know that you hate migrating data, and that you'd rather use a badly thought out model and waste hours with a bad design decision than simply fixing the tables and the existing data. Well, say goodbye to your data migration angst, 'cause baby, its going away.

You are responding to this comment written by Petr Antos on January 30th 2008, 10:12.

Will, I had today discovered your site, superb django-facebook tutorial, lifeflow ... all that amazingly clean and I like your writing style - be sure that I have finally decided to use your lifeflow for my personal sites :-) Thanks a lot for it.

To Migrations - I have exactly this idea how to do migrations as easy as possible; at least during ongoing development on test-database, where isnt lot of data and dumping/reloading into sqlite must be simply very fast. It is interresting, that you simply and shortly described way how to do it using existing features of django - because, I havent heard of it so simply never at any place on the net... :-)

I am so much feel in love with django, because many years ago, I developed application using czech DOS relational database system "PC-FAND" (he died with DOS, grrr), which ahead of time introduced in fact things VERY similar to MVC, ORM (really:-), and I got pathological dependency on this development approach. In this tool, here was possible to "change model" and tool immediatelly restructured real database data according to this change, eventually with warning to losing some data ...

As today, SQL doesnot allow in SQLite3 so easy modifications (ALTER TABLE fields, as I know), it is really best approach to DUMP all data to XML, recreate all from scratch with mods and then load back again.

As project/apps are designed and implemented, there is not so much need to have such flexibility, but things like django-evolution are here too...

... large post, so its obvious, that I desperatelly need its own blog :-)) Thanks again for LIFEFLOW.

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