EXPLAIN

Started by Andy Lewisabout 27 years ago2 messagesgeneral
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#1Andy Lewis
alewis@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)

Thanks

Andy

#2Bruce Momjian
bruce@momjian.us
In reply to: Andy Lewis (#1)
Re: [GENERAL] EXPLAIN

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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