Date: Wed, 18 Jul 2007 21:28:40 +0200
From: Adriaan van Os <postgres@microbizz.nl>
Subject: Re: insert vs select into performance
In-reply-to: <20070718113141.GH12481@mathom.us>
To: pgsql-performance@postgresql.org
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Michael Stone wrote:
> On Tue, Jul 17, 2007 at 10:58:01PM +0200, Thomas Finneid wrote:
>> I am not sure I understand you correctly here, are you saying that 
>> SELECT INTO in 8.1 disables WAL logging and uses just a single fsync 
>> at the end? in that case it means that I could disable WAL as well and 
>> achieve the same performance, does it not?
> 
> Yes. The difference is that the select into optimization just means that 
> if the system crashes the data you're inserting is invalid (and is 
> properly cleaned up), and disabling the WAL means that if the system 
> crashes everything is invalid (and can't be cleaned up).

So, how does one (temporarily) disable WAL logging ? Or, for example, disable WAL logging for a 
temporary table ?

Regards,

Adriaan van Os