Pavel Stehule writes:
2013/8/29 Tom Lane <tgl@sss.pgh.pa.us>
So the question I'm now wondering about is whether this consideration
makes variadic aggregates a bad idea all around, even if we don't have
any built-in ones. Is the risk of user confusion (in the use of their
own aggregate) sufficient reason to reject such a feature?
can be this issue solved by syntax?
In September commitfest is patch for "WITHIN GROUP" where ORDER BY clause
is safety separated from parameters.
That might not be the ugliest syntax the SQL committee ever invented, but
it's right up there. I don't want to go that way, especially not when the
existing precedent for the same feature with regular functions doesn't use
any weird special syntax.

On further reflection, what the "policy" was actually about was not that
we should forbid users from creating potentially-confusing aggregates
themselves, but only that we'd avoid having any *built in* aggregates with
this hazard. So maybe I'm overthinking this, and the correct reading is
just that we should have a policy against built-in variadic aggregates.

    regards, tom lane

Search Discussions

Discussion Posts

Previous

Follow ups

Related Discussions

Discussion Navigation
viewthread | post
posts ‹ prev | 3 of 20 | next ›
Discussion Overview
grouppgsql-hackers @
categoriespostgresql
postedAug 29, '13 at 7:55p
activeAug 31, '13 at 3:02a
posts20
users7
websitepostgresql.org...
irc#postgresql

People

Translate

site design / logo © 2017 Grokbase