Message-ID: <52B46DCD.2070107@optionshouse.com>
Date: Fri, 20 Dec 2013 10:18:21 -0600
From: Shaun Thomas <sthomas@optionshouse.com>
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To: Alvaro Herrera <alvherre@2ndquadrant.com>, Dave Johansen
 <davejohansen@gmail.com>
CC: Scott Marlowe <scott.marlowe@gmail.com>, Jeff Janes
 <jeff.janes@gmail.com>, pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: Recommendations for partitioning?
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On 12/20/2013 09:59 AM, Alvaro Herrera wrote:

> WITH moved AS (
> 	DELETE FROM src WHERE ..
> 	RETURNING *
> ) INSERT INTO dst SELECT * FROM moved;

I know that's effectively an atomic action, but I'd feel a lot more 
comfortable reversing that logic so the delete is based on the results 
of the insert.

WITH saved AS (
     INSERT INTO dst
     SELECT * FROM src WHERE ...
     RETURNING *
)
DELETE FROM src
  WHERE ...;

I'll admit yours is cleaner, though. :)

-- 
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604
312-676-8870
sthomas@optionshouse.com

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