Re: Restriction of windows functions

From: Konstantin Knizhnik <k(dot)knizhnik(at)postgrespro(dot)ru>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: Restriction of windows functions
Date: 2016-06-17 14:39:41
Message-ID: 57640BAD.10400@postgrespro.ru
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 17.06.2016 17:01, Tom Lane wrote:
>
> Certainly it assumes that window is ordered by key and the key type
> supports subtraction, so "text" can not be used here.
> IIRC, the sticking point was defining a reasonably datatype-independent
> (i.e. extensible) notion of distance.

Why it is not possible just to locate "-" or "+ operator for this type?
I do not see any difference here with locating comparison operator
needed for sorting.

--
Konstantin Knizhnik
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Tom Lane 2016-06-17 14:53:36 Re: New design for FK-based join selectivity estimation
Previous Message Tom Lane 2016-06-17 14:26:22 Re: Should phraseto_tsquery('simple', 'blue blue') @@ to_tsvector('simple', 'blue') be true ?