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From: Tom Lane <tgl@sss.pgh.pa.us>
To: =?UTF-8?B?0JDQvdC00YDQtdC5INCW0LjQtNC10L3QutC+0LI=?= <pensnarik@gmail.com>
cc: pgsql-sql@lists.postgresql.org
Subject: Re: FILTER clause for non-aggregate window functions
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=3D?UTF-8?B?0JDQvdC00YDQtdC5INCW0LjQtNC10L3QutC+0LI=3D?=3D <pensnarik@gmai=
l.com> writes:
> Why FILTER is not implemented for non-aggregate functions?

The SQL standard only describes FILTER for aggregates.  I'm not sure
offhand whether it'd be semantically sensible for window functions.
In any case, seems like most of the cases where you'd want it can be
expressed equally well by putting the restriction into WHERE.

			regards, tom lane