Re: date index problems - Mailing list pgsql-hackers

From Gavin Sherry
Subject Re: date index problems
Date
Msg-id Pine.LNX.4.21.0303211602400.6904-100000@linuxworld.com.au
Whole thread Raw
In response to date index problems  ("Christopher Kings-Lynne" <chriskl@familyhealth.com.au>)
Responses Re: date index problems
List pgsql-hackers
On Fri, 21 Mar 2003, Christopher Kings-Lynne wrote:

> This behaviour I find unusual:
> 
> usa=# explain analyze select user_id, plan_next from users_profiles where
> plan_next = '2003-01-01';
>                                                                   QUERY PLAN
> ----------------------------------------------------------------------------
> -------------------------------------------------------------------
>  Index Scan using users_profiles_plan_next_key on users_profiles
> (cost=0.00..614.01 rows=228 width=8) (actual time=0.41..0.41 rows=0 loops=1)
>    Index Cond: (plan_next = '2003-01-01'::date)
>  Total runtime: 0.49 msec
> (3 rows)
> 
> usa=# explain analyze select user_id, plan_next from users_profiles where
> plan_next = '2003-01-01'::date - interval '1 week';
>                                                   QUERY PLAN
> ----------------------------------------------------------------------------
> -----------------------------------
>  Seq Scan on users_profiles  (cost=0.00..1076.08 rows=184 width=8) (actual
> time=109.48..109.48 rows=0 loops=1)
>    Filter: ((plan_next)::timestamp without time zone = '2002-12-25
> 00:00:00'::timestamp without time zone)
>  Total runtime: 109.56 msec
> (3 rows)

I presume the type of plan_next is 'date'. Does casting '2003-01-01'::date
- interval '1 week' to date help?

Gavin



pgsql-hackers by date:

Previous
From: "Christopher Kings-Lynne"
Date:
Subject: Re: date index problems
Next
From: Tom Lane
Date:
Subject: Re: probs with postgres