>>>>> "Tom" == Tom Lane <[EMAIL PROTECTED]> writes:
[snip spec] Just out of curiosity, since I don't have a copy of the spec handy, how does the language for WITH compare to that for views? Tom> I think this is a "must fix" because of the point about volatile Tom> functions --- changing it later will result in user-visible Tom> semantics changes, so we have to get it right the first time. I strongly disagree that this should be a blocking issue - the patch as it stands is an insanely useful feature, allowing many real-world queries to work which simply were not possible before without resorting to procedural code or awkward database designs. Tom> This isn't going to be a particularly simple fix :-(. The basic Tom> implementation clearly ought to be to dump the result of the Tom> subquery into a tuplestore and then have the upper level read Tom> out from that. Which will be a serious pessimization in many common cases if you do it all the time. Googling for examples of non-recursive WITH queries shows that it is very widely used for clarity or convenience, in contexts where you _don't_ want materialization. Recursive WITH queries that self-join the recursion result seem to be rare in practice. -- Andrew (irc:RhodiumToad) -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
