Re: [SQL] what is "cost"?

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От Gregory Holston
Тема Re: [SQL] what is "cost"?
Дата
Msg-id Pine.SUN.3.91.990423172542.17226C-100000@shell
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Ответ на Re: [SQL] what is "cost"?  (Bruce Momjian <maillist@candle.pha.pa.us>)
Ответы Re: [SQL] what is "cost"?
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On Fri, 23 Apr 1999, Bruce Momjian wrote:

> > 
> > Hi All,
> > 
> > I just did an explain and was wondering what is meant by cost.  I just 
> > got a 72.983 cost from a query I found not working.  Any info or pointers 
> > would be appreciated.
> 
> Just added to explain manual page:
> 
>     The cost value is only meaningful to the optimizer in comparing various
>     query plans.
> 
I got the 72.98 on this table while doing a simple "select * from 
publication" meanwhile I got nothing higher than 4 on any other table. Is this 
indicative of a problem?

-Greg


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