From: Uros <uros@sir-mag.com>
To: pgsql-general@postgresql.org
Subject: Optimizing query
Date: Wed, 19 Nov 2003 11:41:41 +0100
Message-ID: <81222392078.20031119114141@sir-mag.com> (raw)
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.
--
Best regards,
Uros mailto:uros@sir-mag.com
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To: pgsql-general@postgresql.org
Cc: uros@sir-mag.com
Subject: Re: Optimizing query
In-Reply-To: <81222392078.20031119114141@sir-mag.com>
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