On Wed, Feb 3, 2010 at 3:37 AM, Pablo Castro <Pablo.Castro@microsoft.com>wrote:
>
> > > I prefer to leave composite keys to a future version.
>
> I don't think we can get away with this. For indexes this is quite common
> (if anything else to have stable ordering when the prefix of the index has
> repeats). Once we have it for indexes the delta for having it for primary
> keys as well is pretty small (although I wouldn't oppose leaving out
> composite primary keys if that would help scope the feature).
>
After talking to some of our web app teams at Google, I'm going to have to
strongly agree with this. As far as we can tell, there's no efficient way
to emulate this behavior in JavaScript and it's a pretty common use case.