2008/12/21 Hitoshi Harada <umi.tan...@gmail.com>: > 2008/12/20 Tom Lane <t...@sss.pgh.pa.us>: >> I've been studying the grammar for the windowing patch a bit. It seems >> to me that the <existing window name> option for <window specification> >> got left out. I think that WindowDef needs to have two name fields, >> one for the name (if any) defined by the window definition, and one >> for the referenced window name if any. Also the "OVER name" syntax >> seems like it maps to a referenced window name not a defined window >> name. > > I completely missed this issue. If the <existing window name> is > allowed in <window clause>, then does it mean this is possible? > > SELECT row_number() OVER w2 FROM t > WINDOW w1 AS (PARTITION BY grp), w2(w1) > > And what if w1 refers to w2 and w2 refers to w1 cyclicly? And from > what I read the spec, it seems to me that it effects only frame clause > which is unlikely implemented for 8.4, because if <existing window > name) is specified then <partition clause> and <order by clause> are > both permitted in the window definition.
both "not" permitted in the window definition. Sorry for my mistake. -- Hitoshi Harada -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
