> Courtenay wrote:
> > > >>>> Is this something that would be a useful addition to Rails core?
> > > >>>> I'd appreciate some feedback / criticism.

> > > >>> Wow, this looks really complicated. I think the solution with all

> > Why can't we just have a ParallelMigration (IndependentMigration)
> > subclass that doesn't check for duplicates in the numbering?

> > My most common use case is where I'm taking someone else's app,
> > checking it in locally with svk, adding some fields or models here and
> > there, but my changes are really in parallel with the original
> > changes.

> > In that case I'd have

> > 067_create_monkey_table
> > 068_add_banana_field_to_monkey.rb
> > 068_add_product_table.rb
> > 069_add_monkey_field_to_product

> > We would assume from looking at the numbering that both 068_* are
> > somewhat dependent on 067, and come before 069.  It would work only if
> > they are both this new independent migration class.

> > This opens up a whole new metaphor for thinking about migrations;
> > independent migration classes. So you'd add a few tables all at once,
> > but instead of putting then sequentially or in the same file, you make
> > 3 parallel files.

> > I don't know if this solves the "long-running" branches issue, but
> > it's certainly simple..

> I spend a lot of time doing branch-based development, where you make a
> branch for each major feature.  It's powerful, but merging migrations
> is horrible.

> What happens if you migrate up or down and you never applied one of the
> parallel patches? or, if you merge someone's code and it contains old
> migrations that you've progressed over?
> For example, you're at version=52 but someone else's merged code adds
> 47 and 51, which you haven't run..   In this case you just migrate down
> and up again..

> What if you only applied one of the migrations 068, but you want to go
> down anyway?  I guess the IndependentMigration would have to specify if
> you can skip it..otherwise, do what we all do when migrations half-run,
> go in, comment out the offending code, migrate down, and uncomment it
> again.