2008/10/29 Tom Lane <[EMAIL PROTECTED]>: > "Hitoshi Harada" <[EMAIL PROTECTED]> writes: >> Can "ROWS" be reserved_keyword? > >> In window specifications, we have > >> OVER (ORDER BY expr_list [(ROWS|RANGE) ... ]) > >> and currently "ROWS" is not reserved so bison is confused with cases >> of "ROWS" included in expr_list and in FRAME clause. Because there is >> no delimiter between ORDER BY clause and FRAME (that is (ROWS | >> RANGE)) clause, "ROWS" can be in expr_list as a_expr. > > Right offhand, I don't see any alternative but to make both ROWS and > RANGE reserved. It's pretty annoying since that might break existing > applications that have been using these as identifiers, but the SQL > committee seems to care little about that :-( > > BTW, finding this sort of problem is exactly why ignoring shift/reduce > conflicts is a bad idea. You would've ended up with unexpected > behaviors given the wrong input. >
I see it now. This is so good study to me, though it spent me much time. Thanks anyway. Regards, -- 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
