From: sathiya psql <sathiya.psql@gmail.com>
To: pgsql-performance@postgresql.org
Subject: count * performance issue
Date: Thu, 6 Mar 2008 11:13:01 +0530
Message-ID: <f966c2ee0803052143k4570d771o6c300647d3b987d@mail.gmail.com> (raw)
In-Reply-To: <f966c2ee0803052142l6a105678jfe2da92a0d9371@mail.gmail.com>
References: <f966c2ee0803052142l6a105678jfe2da92a0d9371@mail.gmail.com>
count(*) tooks much time...
but with the where clause we can make this to use indexing,... what where
clause we can use??
Am using postgres 7.4 in Debian OS with 1 GB RAM,
am having a table with nearly 50 lakh records,
it has more than 15 columns, i want to count how many records are there, it
is taking nearly 17 seconds to do that...
i know that to get a approximate count we can use
SELECT reltuples FROM pg_class where relname = TABLENAME;
but this give approximate count, and i require exact count...
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To: pgsql-performance@postgresql.org
Cc: sathiya.psql@gmail.com
Subject: Re: count * performance issue
In-Reply-To: <f966c2ee0803052143k4570d771o6c300647d3b987d@mail.gmail.com>
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