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Date: Thu, 19 Apr 2012 12:55:41 +0200
From: Dennis <dennis.verbeek@victorem.com>
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To: Tom Lane <tgl@sss.pgh.pa.us>
CC: "pgsql-sql@postgresql.org" <pgsql-sql@postgresql.org>
Subject: Re: Uniform UPDATE queries
References: <4F8E936A.9050303@victorem.com> <4420.1334766267@sss.pgh.pa.us>
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Hello Tom,

The example you have given is EXACTLY why something like CURRENT is needed to limit the number of 
unique queries or prepared statements. (or to do a selection of all values before an update meaning 
two executed queries.)

regards,.

Dennis

On 04/18/2012 06:24 PM, Tom Lane wrote:
> Dennis<dennis.verbeek@victorem.com>  writes:
>> When a query is written to update a table, the usual process is to list all the columns that need
>> updating. This could imply the creation of many possible queries for many columns. In an effort to
>> keep the UPDATE queries more uniform, less number of unique queries, a keyword similar to DEFAULT,
>> let's say CURRENT, is required to indicate that the current value must not change.
> No it isn't.  Just write the name of the column, eg
>
> 	update mytable set x = x, y =<new value>, z = z where ...
>
> There's no reason to invent nonstandard syntax for this.
>
> 			regards, tom lane
>
>
>