Re: Items with some, but not all, fields in common

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Items with some, but not all, fields in common

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Join Date: Mar 2008

Posts: 25

Reputation: blater is an unknown quantity at this point

Rep Power: 1

Solved Threads: 7

blater

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Re: Items with some, but not all, fields in common

Apr 24th, 2008

I wouldn't recommend seperate tables for each of the flavor types. Here are two possible methods....

1) Your first choice - put then into one table. This is relationally correct as the flavor-specific attributes have the flavor as the determinant (i.e they really do belong to the flavor).
i.e

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ioPoint
--------
ioPointID
flavorID

ioPointFlavor
-------------
flavorID
port
channel
foo
bar
baz
:
:
etc

If there are a very large number of these attributes you could do the following instead:

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ioPoint
--------
ioPointID
flavorID

ioPointFlavor
-------------
flavorID
port
channel


ioPointFlavorAttributes
--------------------------
flavorID
attributeType  string
attributeValue string

Here a list of zero or more attributes and values is associated with each ioPointFlavor.
Depending on your requirements this may make your reporting easier, although maintenance of the will require more programming.
It would make it easy to add new types of flavor attribute. Note you'd probably want a flavor attributeType lookup table as well.

http://www.inverse2.com

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Re: Items with some, but not all, fields in common

Items with some, but not all, fields in common

Re: Items with some, but not all, fields in common