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Re: FK relations...

From: MarkP28665 <markp28665_at_aol.com>
Date: 1997/02/27
Message-ID: <19970227160601.LAA28741@ladder02.news.aol.com>#1/1

>>

I was wondering if Oracle can do an optimization so that foreign keys are stored as fake keys rather than the actual fields themselves. This way cascade updates on key fields would not need to be replicated. I know that this could be done manually, but if the database suports it, that seems like a better design way to go. <<

I am not sure I understand the benefit of this. Oracle uses indexes to support the foreign key checks/relationships. If you update a column in a table that has a foreign key constraint on it then referenced column must be cheched for the new value being valid. Storing a fake key in the table would take space and require overhead for changes made to the referenced table. If just seems you would end up moving the costs of checking referenced columns from one operation to another.

As I said I am not sure I understand what you are asking so if my conclusions miss the mark then maybe you could explain a little more.

Mark Powell -- The only advise that counts is the advise that you follow so follow your own advise Received on Thu Feb 27 1997 - 00:00:00 CST

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