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Re: Nearest Common Ancestor Report (XDb1's $1000 Challenge)

From: Neo <neo55592_at_hotmail.com>
Date: 7 Jun 2004 19:56:58 -0700
Message-ID: <4b45d3ad.0406071856.199b51ca@posting.google.com>


> The first challenge was much too easy for my liking.

Besides the redundancy in the schema, the provided solutions stores redundant data. Using either #1 or #2, enter the equivalent of the following XDb1 script.

color isa thing.
brown isa color.

person isa thing.
john isa person.
john's color is brown.
mary isa person.
mary's color is brown.

Although brown appears three times in the script, XDb1 normalizes the second two by making them references to the first one. There is only one brown in XDb1's db. Using RM#1 or #2, brown is actually stored three separate times. This is redundant and unnormalized. Received on Mon Jun 07 2004 - 21:56:58 CDT

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