On Thu, 2011-11-17 at 17:10 -0500, Tom Lane wrote: > Applied, thanks. These comments aren't quite what I'd hoped for though. > What I'm lacking is the conceptual context, ie, why is a > less-equal-greater primitive for bounds a good thing? It seems like > when you consider the four possible directional (lower/upper) > combinations, the same result from range_cmp_bounds means something > different in each case, and I find that confusing. I wonder whether > functions defined along set-theoretic lines (this bound is strictly > weaker or stronger than this other one, or these bounds together define > an empty or singleton or non-singleton set) might be more transparent.
I think it comes down to how helpful it is to define higher-level functions in terms of range_cmp_bounds versus some other function (or set of functions). range_cmp_bounds seemed to work out fairly well for most of the operators, and it was the best that I came up with. The nice thing about it is that it can compare a lower bound to another lower bound, or to an upper bound. Then again, perhaps I tried to hard to unify those concepts, and it just led to complexity? I'm open to suggestion. Regards, Jeff Davis -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers