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Re: Removing SORTFUNC_LT/REVLT

From: Martijn van Oosterhout <kleptog(at)svana(dot)org>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Greg Stark <gsstark(at)mit(dot)edu>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Removing SORTFUNC_LT/REVLT
Date: 2005-12-31 20:56:30
Message-ID: 20051231205628.GB634@svana.org (view raw or flat)
Thread:
Lists: pgsql-hackers
On Sat, Dec 31, 2005 at 02:54:18PM -0500, Tom Lane wrote:
> The example of case-insensitive sorting suggests that we need to assume
> that sort comparison functions can make finer-grained comparisons than
> the associated "equals" operator does.  The current infrastructure
> forces these to be exactly the same, but as long as we're busy
> reinventing stuff, we could have two comparison functions associated
> with a btree opclass: one that mimics the operators' behavior and one
> that makes finer-grained comparisons and defines the actual sort order.

Indeed, that's exactly the thought I had this afternoon, distiguish a
"collation" and a "comparison" function. It's certainly a lot easier to
implement than anything else I could think of....

Have a great New Year everyone,
-- 
Martijn van Oosterhout   <kleptog(at)svana(dot)org>   http://svana.org/kleptog/
> Patent. n. Genius is 5% inspiration and 95% perspiration. A patent is a
> tool for doing 5% of the work and then sitting around waiting for someone
> else to do the other 95% so you can sue them.

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