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Re: Performance UPDATE/INSERT

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am  11.04.2006, um 12:15:41 +0200 mailte Alban Hertroys folgendes:
> MG wrote:
> >I have to improve the performance of the UPDATES and I was wondering why 
> >the UPDATEs need twice as long as the INSERTs.
> 
> IIRC, an UPDATE is a DELETE/INSERT combo. That's because the original 
> record still needs to be visible to other existing transactions (because of 
> MVCC). You can't change its data but need to create a new record instead 
> and mark the original as obsolete.

Correctly, and thats why we need VACUUM to clean the space on the disk.


HTH, Andreas
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Andreas Kretschmer    (Kontakt: siehe Header)
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