[Rails-core] some (long) thoughts on migrations

[David Heinemeier Hansson]

> So, I figured I'd pass this along in case this was of interest to
> someone else.

I appreciate your thinking on this, Rick, but I think that the trouble
migrations display in this case is simply a symptom of infrequent
integration. Just like you get svn conflicts if you stay off the
committing for too long. I think the solution is simply to integrate
more often, not to add additional software.

> But, this doesn't catch everything (the before_save example is unhelped, e.g.).
> Ultimately, the developer can't (and shouldn't have to) predict what the future
> is going to bring, and shouldn't have to code around this sort of problem.

If this turns out to be a real problem for you (I've never seen it in
the wild), I'd encourage tying marrying migrations with svn updates.
So you could have a script that does "svn co rev 1; rake migrate; svn
co rev 2; rake migrate". If that's something that turns out to be
useful, please do turn it into a plugin.
--
David Heinemeier Hansson
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