From: Bruce Momjian <pgman@candle.pha.pa.us>
Message-Id: <200207161538.g6GFcS925954@candle.pha.pa.us>
Subject: Re: [SQL] line datatype
In-Reply-To: <3D343BEA.1B51B9CD@fourpalms.org>
To: Thomas Lockhart <lockhart@fourpalms.org>
Date: Tue, 16 Jul 2002 11:38:28 -0400 (EDT)
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Tim Hart <tjhart@mac.com>,
	PostgreSQL-development <pgsql-hackers@postgresql.org>
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Thomas Lockhart wrote:
> ...
> > > We do need a solution for exact dump/reload of floating-point data,
> > > but I don't see why the lack of it should be reason to disable access
> > > to the LINE type.
> > I don't understand why dumping the two point values isn't sufficient.
> 
> Which two point values? LINE is handled as an equation, not as points,
> unlike the LSEG type which has two points.

Well, the \dT documentation used to show line as two points, so I
assumed that was how it was specified.

> One possibility is to have the external representation *be* the same as
> LSEG, then convert internally. Then we need to decide how to scale those
> points; maybe always using a unit vector is the right thing to do...

No one likes entering an equation.  Two points seems the simplest.

-- 
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