From: Tom Lane <tgl@sss.pgh.pa.us>
To: Daniel Kalchev <daniel@digsys.bg>
Cc: pgsql-hackers@postgresql.org
Subject: Re: again on index usage
Date: Tue, 08 Jan 2002 09:37:11 -0500
Message-ID: <23405.1010500631@sss.pgh.pa.us> (raw)
In-Reply-To: <200201080922.LAA02480@dcave.digsys.bg>
References: <200201080922.LAA02480@dcave.digsys.bg>
Daniel Kalchev <daniel@digsys.bg> writes:
> Same result (sorry, should have included this originally):
> Aggregate (cost=47721.72..47721.72 rows=1 width=8)
> -> Seq Scan on iplog_gate200112 (cost=0.00..47579.54 rows=56873 width=8)
>>> If you say "set enable_seqscan to off", does that change the plan?
> Aggregate (cost=100359.71..100359.71 rows=1 width=8)
> -> Index Scan using iplog_gate200112_ipdate_idx on iplog_gate200112
> (cost=0.00..100217.52 rows=56873 width=8)
So, what we've got here is a difference of opinion: the planner thinks
that the seqscan will be faster. How many rows are actually selected
by this WHERE clause? How long does each plan actually take?
regards, tom lane
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To: pgsql-hackers@postgresql.org
Cc: tgl@sss.pgh.pa.us, daniel@digsys.bg
Subject: Re: again on index usage
In-Reply-To: <23405.1010500631@sss.pgh.pa.us>
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