Date: 26 Oct 2005 06:45:18 -0700
Message-ID: <1130334318.730554.140170_at_f14g2000cwb.googlegroups.com>
Imagine you were knocking up a simple table of animals and their predominant colors. Something of the order:
animal | color
swan | white lion | yelloworanguatan | orange
----------------------
Consider also that some animals that have multicolored fur. For
instance a zebra is black and white. Keeping the table nice and
normalized yields:
animal | color
swan | white
lion | yellow
oranguatan | orange
zebra | black
zebra | white
----------------------
Now you find out that while most swans are white, there are some swans, although a minority, that are completely black. You can't encode that into table without introducing a new column to identify an individual instance of an animal, or you will not be able to distinguish between an entry which is multi-colored (the zebras) and an entry which is either completely one color or the other (the swans).
Many thanks, Jason. Received on Wed Oct 26 2005 - 15:45:18 CEST