Re: Window Functions: v07 APIs and buffering strateties

On Tue, Oct 28, 2008 at 12:38:09PM -0400, Tom Lane wrote:
> "Hitoshi Harada" <umi.tanuki@gmail.com> writes:
> > 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 :-(

Given that the only problematic case is if expr_list ends with a
postfix operator, wouldn't it be sufficient to simply decree that in
that case you need parentheses? Seems a lot less painful than adding
two reserved words.

Have a nice day,
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Please line up in a tree and maintain the heap invariant while
> boarding. Thank you for flying nlogn airlines.