From: Bruce Momjian <maillist@candle.pha.pa.us>
To: alewis@mpsi.net
Cc: pgsql-general@postgreSQL.org
Subject: Re: [GENERAL] EXPLAIN
Date: Wed, 3 Feb 1999 18:11:00 -0500 (EST)
Message-ID: <199902032311.SAA27570@candle.pha.pa.us> (raw)
In-Reply-To: <Pine.LNX.4.05.9902031700001.20312-100000@shell.mpsi.net>
> When I do an explain what does the cost, size and width mean that is returned?
>
> Seq Scan on apts (cost=249.95 size=2362 width=468)
Cost is a computed value by the optimizer of how long it will execute.
It is meaningful only in comparison to there queries. size if the
number of rows estimated to return. width is the number of bytes per
row returned.
--
Bruce Momjian | http://www.op.net/~candle
maillist@candle.pha.pa.us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026
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To: pgsql-general@postgresql.org
Cc: maillist@candle.pha.pa.us, alewis@mpsi.net
Subject: Re: [GENERAL] EXPLAIN
In-Reply-To: <199902032311.SAA27570@candle.pha.pa.us>
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