Re: Hash support for arrays - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: Hash support for arrays
Date
Msg-id 1288722794-sup-9633@alvh.no-ip.org
Whole thread Raw
In response to Re: Hash support for arrays  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Excerpts from Tom Lane's message of mar nov 02 15:21:31 -0300 2010:

> What concerns me about that is that it tends to push the bits to the
> left --- I think the effects of the earlier inputs are going to overflow
> out as you incorporate a lot of newer inputs.  What you want is a scheme
> where every input item affects all the bits of the final result about
> equally, and my gut feeling is this doesn't provide that.

Ahh, now I understand what you meant with "rotating" the bits in the
original email in this thread.  You're not simply shifting.  Clever.

-- 
Álvaro Herrera <alvherre@commandprompt.com>
The PostgreSQL Company - Command Prompt, Inc.
PostgreSQL Replication, Consulting, Custom Development, 24x7 support


pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: Hash support for arrays
Next
From: Robert Haas
Date:
Subject: Re: Hash support for arrays