Re: Optimizing query - Mailing list pgsql-general

From Rob Sell
Subject Re: Optimizing query
Date
Msg-id 003201c3aea3$33cc38b0$640101c0@rob
Whole thread Raw
In response to Re: Optimizing query  (Shridhar Daithankar <shridhar_daithankar@myrealbox.com>)
Responses Re: Optimizing query
List pgsql-general
Greetings all,

Yesterday I upgraded from 7.3 to 7.4 now psql doesn't work! I get the
following error.

psql: relocation error: psql: undefined symbol: get_progname

Any ideas out there?

Rob

-----Original Message-----
From: pgsql-general-owner@postgresql.org
[mailto:pgsql-general-owner@postgresql.org] On Behalf Of Shridhar Daithankar
Sent: Wednesday, November 19, 2003 6:23 AM
To: Uros
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] Optimizing query

Uros wrote:

> Hello!
>
> I have some trouble getting good results from my query.
>
> here is structure
>
> stat_views
> id        | integer
> id_zone   | integer
> created   | timestamp
>
>
> I have btree index on created and also id and there is  1633832 records in
> that table
>
> First of all I have to manualy set seq_scan to OFF because I always get
> seq_scan. When i set it to off my explain show:
>
> explain SELECT count(*) as views FROM stat_views WHERE id = 12;
>                                              QUERY PLAN
>
----------------------------------------------------------------------------
------------------------
>  Aggregate  (cost=122734.86..122734.86 rows=1 width=0)
>    ->  Index Scan using stat_views_id_idx on stat_views
(cost=0.00..122632.60 rows=40904 width=0)
>          Index Cond: (id = 12)
>
> But what I need is to count views for some day, so I use
>
> explain SELECT count(*) as views FROM stat_views WHERE date_part('day',
created) = 18;
>
>                                      QUERY PLAN
>
----------------------------------------------------------------------------
--------
>  Aggregate  (cost=100101618.08..100101618.08 rows=1 width=0)
>    ->  Seq Scan on stat_views  (cost=100000000.00..100101565.62 rows=20984
width=0)
>          Filter: (date_part('day'::text, created) = 18::double precision)
>
>
> How can I make this to use index and speed the query. Now it takes about
12
> seconds.

Can you post explain analyze for the same?

  Shridhar



---------------------------(end of broadcast)---------------------------
TIP 4: Don't 'kill -9' the postmaster


pgsql-general by date:

Previous
From: Dave Cramer
Date:
Subject: Re: Point-in-time data recovery - v.7.4
Next
From: Carmen Gloria Sepulveda Dedes
Date:
Subject: Problem with exec sql include