Skip site navigation (1) Skip section navigation (2)

Re: Common Table Expressions (WITH RECURSIVE) patch

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Hitoshi Harada" <umi(dot)tanuki(at)gmail(dot)com>
Cc: "Greg Stark" <stark(at)enterprisedb(dot)com>, "Dimitri Fontaine" <dfontaine(at)hi-media(dot)com>, "Jeff Davis" <pgsql(at)j-davis(dot)com>, "Tatsuo Ishii" <ishii(at)postgresql(dot)org>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Common Table Expressions (WITH RECURSIVE) patch
Date: 2008-10-01 19:53:11
Message-ID: 27939.1222890791@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-hackers
"Hitoshi Harada" <umi(dot)tanuki(at)gmail(dot)com> writes:
>> I hadn't realized that this would be relevant to window functions.
>> Now that I know that, I propose fixing tuplestore for multiple
>> positions and committing it separately, before I go back to the CTE
>> patch.  Then Hitoshi-san will have something he can work with too.

> Yes, tuplestore multiple positioning will give the greate help to the
> window function. Ideally, it is better that tuplestore'd have all the
> positions and have some kind of capability to discard old rows so that
> it can stay in TSS_MEM, which helps window function's sliding frame.

Okay, there's a patch in CVS HEAD that works this way.  Let me know if
it needs further tweaking for your purposes.

			regards, tom lane

In response to

Responses

pgsql-hackers by date

Next:From: Tom LaneDate: 2008-10-01 20:06:16
Subject: Re: Block-level CRC checks
Previous:From: Paul SchlieDate: 2008-10-01 19:43:34
Subject: Re: Block-level CRC checks

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group