Re: [GENERAL] EXPLAIN - Mailing list pgsql-general

From Bruce Momjian
Subject Re: [GENERAL] EXPLAIN
Date
Msg-id 199902032311.SAA27570@candle.pha.pa.us
Whole thread Raw
In response to EXPLAIN  (Andy <alewis@mpsi.net>)
List pgsql-general
>  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.


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