From: "Dave Dutcher" <dave@tridecap.com>
To: "'PFC'" <lists@peufeu.com>
Cc: <pgsql-performance@postgresql.org>
Subject: Re: INSERT OU UPDATE WITHOUT SELECT?
Date: Tue, 30 May 2006 17:54:00 -0500
Message-ID: <039201c6843b$f11eeaf0$8300a8c0@tridecap.com>
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In-Reply-To: <op.tadyc1jwcigqcu@apollo13>
Importance: Normal

What I do when I'm feeling lazy is execute a delete statement and then
an insert.  I only do it when I'm inserting/updating a very small number
of rows, so I've never worried if its optimal for performance.  Besides
I've heard that an update in postgres is similar in performance to a
delete/insert.


> -----Original Message-----
> From: pgsql-performance-owner@postgresql.org 
> [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of PFC
> Sent: Tuesday, May 30, 2006 5:35 PM
> To: Jonah H. Harris; Waldomiro
> Cc: pgsql-performance@postgresql.org
> Subject: Re: [PERFORM] INSERT OU UPDATE WITHOUT SELECT?
> 
> 
> > PostgreSQL does not support MERGE at the moment, sorry.
> 
> 	Issue an UPDATE, and watch the rowcount ; if the 
> rowcount is 0, issue an  
> INSERT.
> 	Be prepared to retry if another transaction has 
> inserted the row  
> meanwhile, though.
> 
> 	MERGE would be really useful.
> 
> 
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