Date: Mon, 11 Jan 2010 12:25:26 +0100
To: "Robert Haas" <robertmhaas@gmail.com>
Subject: Re: PG optimization question
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Cc: "Hannu Krosing" <hannu@2ndquadrant.com>, Nickolay <nitro@zhukcity.ru>,
	pgsql-performance@postgresql.org
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On Sun, 10 Jan 2010 19:45:32 +0100, Robert Haas <robertmhaas@gmail.com>  
wrote:

> 2010/1/10 Pierre Frédéric Caillaud <lists@peufeu.com>:
>>
>>> If you transfer (delete from staging, insert into archive) in one
>>> transaction , then it will be always visible in exactly one of them,
>>> and exatly once in a view over both staging and archive(s).
>>
>>        Does the latest version implement this :
>>
>> INSERT INTO archive (...) DELETE FROM staging WHERE ... RETURNING ...
>
> No.  There are no plans to support that, though there are proposals to  
> support:
>
> WITH x AS (DELETE FROM staging WHERE ... RETURNING ...) INSERT INTO
> archive (...) SELECT ... FROM x
>
> I'm not sure how much that will help though since, in the designs so
> far discused, the tuples won't be pipelined.
>
> ...Robert
>

	Yeah, but it's a lot more user-friendly than SELECT FOR UPDATE, INSERT  
SELECT, DELETE...