"Armstrong's axioms" augmentation - help plz

From: love boat via DBMonster.com <forum_at_DBMonster.com>
Date: Mon, 07 Mar 2005 08:35:07 GMT
Message-ID: <d6f431381d204e5f82d2456953862cd8_at_DBMonster.com>



I understand the Augmentation rule:
{ X -> Y } |= XZ -> YZ

but I don't understand why the rule can also be stated as:

{ X -> Y } |= XZ -> Y

Why is this?

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Received on Mon Mar 07 2005 - 09:35:07 CET

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