On 23 May 2016 at 17:01, Jeff Davis <pg...@j-davis.com> wrote: > On Fri, May 20, 2016 at 1:41 PM, David G. Johnston > <david.g.johns...@gmail.com> wrote: >> How does the relatively new FILTER clause play into this, if at all? > > My interpretation of the standard is that FILTER is not allowable for > a window function, and IGNORE|RESPECT NULLS is not allowable for an > ordinary aggregate. >
That may be so, but we already support FILTER for all windows functions as well as aggregates: https://www.postgresql.org/docs/current/static/sql-expressions.html#SYNTAX-AGGREGATES https://www.postgresql.org/docs/current/static/sql-expressions.html#SYNTAX-WINDOW-FUNCTIONS so to be clear, what we're talking about here is just supporting SQL standard syntax for window functions, rather than adding any new functionality, right? > So if we support IGNORE|RESPECT NULLS for anything other than a window > function, we have to come up with our own semantics. > Given that we can already do this using FILTER for aggregates, and that IGNORE|RESPECT NULLS for aggregates is not part of the SQL standard, I see no reason to support it. Regards, Dean -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
