Re: [8.1.4] Create index on timestamp fails - Mailing list pgsql-general

From Alvaro Herrera
Subject Re: [8.1.4] Create index on timestamp fails
Date
Msg-id 20060823130735.GC1963@alvh.no-ip.org
Whole thread Raw
In response to Re: [8.1.4] Create index on timestamp fails  (Arturo Perez <aperez@hayesinc.com>)
Responses Re: [8.1.4] Create index on timestamp fails  (Karsten Hilbert <Karsten.Hilbert@gmx.net>)
List pgsql-general
Arturo Perez wrote:
>
> On Aug 22, 2006, at 5:35 PM, Tom Lane wrote:

> >I seriously doubt that.  date_part on a timestamptz is stable, not
> >immutable, and AFAICT has been marked that way since 7.3.  The problem
> >is that the results depend on your current TimeZone setting --- for
> >instance, 2AM 2006-01-01 in London is 9PM 2005-12-31 where I live.
> >
> >If you only need day precision, try storing entry_date as a date
> >instead
> >of a timestamptz.  Or perhaps consider timestamp without tz.  But you
> >need something that's not timezone-dependent to make this work.
>
> Ah, I knew it was something I was overlooking.  Thanks a ton.  We need
> sub-day granularity (it's for a sort of weblog).  Without a TZ sounds
> llke a winner.

Another idea would be to separate the date column (which would have the
index) from the time column (which would have the timezone).  The
timezone is important -- if you have "bloggers" from all around the
world you're gonna have serious problems with the archived time.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

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