Horton

Re: wip: functions median and percentile

Pavel Stehule <pavel.stehule@gmail.com>

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From: Pavel Stehule <pavel.stehule@gmail.com>
To: Peter Eisentraut <peter_e@gmx.net>
Cc: Greg Stark <gsstark@mit.edu>, Tom Lane <tgl@sss.pgh.pa.us>, Dean Rasheed <dean.a.rasheed@gmail.com>, Hitoshi Harada <umi.tanuki@gmail.com>, Robert Haas <robertmhaas@gmail.com>, David Fetter <david@fetter.org>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2010-10-13T10:56:06Z
Lists: pgsql-hackers 
2010/10/13 Pavel Stehule <pavel.stehule@gmail.com>:
> 2010/10/13 Peter Eisentraut <peter_e@gmx.net>:
>> On mån, 2010-10-11 at 20:46 +0200, Pavel Stehule wrote:
>>> The problem is in interface. The original patch did it, but I removed
>>> it. We cannot to unsure immutability of some parameters now.
>>
>> How about you store the "immutable" parameter in the transition state
>> and error out if it changes between calls?
>>
>
> yes, it's possibility. Now I looking there and I see the as more
> important problem the conformance with ANSI SQL. see my last post.
> There can be a kind of aggregate functions based on tuplesort.

more - all these functions needs to solve same problem with planner
and hash agg. So maybe is time to add a flag ISTUPLESORTED to pg_proc
and add solve these functions together.

Pavel

>
> Regards
>
> Pavel
>
>
>>
>