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From: Gary Fu <gfu@sigmaspace.com>
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Subject: polygon overlay
Date: Tue, 31 Aug 2010 17:14:24 -0400
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Hi,

I don't see any overlap between the polygon and the box in the following 
sql. Can anyone explain why it returns 't'?

  select polygon(path '((0,0),(10,10),(20,10),(10,0))') && polygon(box 
'((16,0),(17,1))');
  ?column?
----------
  t
(1 row)

Thanks,
Gary