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understanding output from Explain

This is a discussion on understanding output from Explain within the Pgsql General forums, part of the PostgreSQL category; --> "Seq Scan on" - is this just a FULL TABLE scan? I'm familiar with Oracles explain plans and terminology. ...


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  #1 (permalink)  
Old 04-09-2008, 03:11 PM
Tom Allison
 
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Default understanding output from Explain

"Seq Scan on" - is this just a FULL TABLE scan?

I'm familiar with Oracles explain plans and terminology.
But not so much so with psql...

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  #2 (permalink)  
Old 04-09-2008, 03:11 PM
A. Kretschmer
 
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Default Re: understanding output from Explain

am Sun, dem 22.04.2007, um 9:43:32 -0400 mailte Tom Allison folgendes:
> "Seq Scan on" - is this just a FULL TABLE scan?


Yes.


Andreas
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Andreas Kretschmer
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TIP 9: In versions below 8.0, the planner will ignore your desire to
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  #3 (permalink)  
Old 04-09-2008, 03:13 PM
tom
 
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Default Re: understanding output from Explain

Is there a tutorial on this stuff?
I did check the Really Fine Manual and they said explain plans are
beyond the scope RTFM.



On Apr 22, 2007, at 10:36 AM, A. Kretschmer wrote:

> am Sun, dem 22.04.2007, um 9:43:32 -0400 mailte Tom Allison
> folgendes:
>> "Seq Scan on" - is this just a FULL TABLE scan?

>
> Yes.
>
>
> Andreas
> --
> Andreas Kretschmer
> Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header)
> GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
>
> ---------------------------(end of
> broadcast)---------------------------
> TIP 9: In versions below 8.0, the planner will ignore your desire to
> choose an index scan if your joining column's datatypes do not
> match



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http://www.postgresql.org/docs/faq

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