Message-ID: <4C9AD104.2030904@2ndquadrant.com>
Date: Thu, 23 Sep 2010 00:01:08 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: gnuoytr@rcn.com
CC: pgsql-performance@postgresql.org
Subject: Re: Useless sort by
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gnuoytr@rcn.com wrote:
> Spoken like a dyed in the wool COBOL coder.  The RM has no need for order; it's set based.  I've dabbled in PG for some time, and my sense is increasingly that PG developers are truly code oriented, not database (set) oriented.  
>   

I can't tell if you meant for this to be insulting or my reading it that 
way is wrong, but it certainly wasn't put in a helpful tone.  Let me 
summarize for you.  You've been told that putting ORDER BY into a view 
is a generally poor idea anyway, that it's better to find ways avoid 
this class of concern altogether.  There are significant non-obvious 
technical challenges behind actually implementing the behavior you'd 
like to see; the concerns raised by Tom and Maciek make your idea 
impractical even if it were desired.  And for every person like yourself 
who'd see the benefit you're looking for, there are far more that would 
find a change in this area a major problem.  The concerns around 
breakage due to assumed but not required aspects of the relational model 
are the ones the users of the software will be confused by, not the 
developers of it.  You have the classification wrong; the feedback 
you've gotten here is from the developers being user oriented, not 
theory oriented or code oriented. 

-- 
Greg Smith, 2ndQuadrant US greg@2ndQuadrant.com Baltimore, MD
PostgreSQL Training, Services and Support  www.2ndQuadrant.us
Author, "PostgreSQL 9.0 High Performance"    Pre-ordering at:
https://www.packtpub.com/postgresql-9-0-high-performance/book