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In-Reply-To: <20030207080420.2131718332@cheetah.webtribe.net>
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Date: Fri, 7 Feb 2003 09:36:54 -0000 (GMT)
Subject: Re: which will be faster? w/ or w/o indices
From: dev@archonet.com
To: val@webtribe.net
Cc: pgsql-sql@postgresql.org
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> I understand that if you are importing data into the database
> that this will go faster if there are no indices against the
> target table.
>
> If I want to run this statement:
> INSERT INTO table_a SELECT * from table_b WHERE value_1 BETWEEN
> X AND Y;
> is it best to do that with or without indices?

Can't really say without testing - it'll depend on the size of the various
tables, X and Y disk speeds etc. The only suggestion I can make is to try
an EXPLAIN (Reference manual, SQL commands) with and without
ENABLE_SEQSCAN off (Admin guide ch 3.2).


- Richard Huxton