Tom> In order to support the spec *exactly*, we would have to.
Tom> For instance we cannot presently tell the difference between
Tom> '13 months' and '1 year 1 month' ... they both end up stored
Tom> as '13 months'. I can't say that I find this very important,
Tom> but it does put limits on how exactly we can emulate the
Tom> spec.
Which is where my comment about EXTRACT comes in. They can both be
stored as 13 months, but EXTRACT (MONTH FROM ...) should return 1
month or 13 months as appropriate. Surely this isn't a problem, you
know the type of the interval?
So you _can_ emulate the spec, you just don't use the same internal
representation that a naive implementation of the spec would...
-roy