Given a relational schema r(A, B, C, D), does A BC logically imply A B

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Given a relational schema r(A, B, C, D), does A →→ BC logically imply A →→ B and A →→ C? If yes prove it, or else give a counter example.

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Database System Concepts

ISBN: 9780078022159

7th Edition

Authors: Abraham Silberschatz, Henry F. Korth, S. Sudarshan

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Question Posted: Jun 13, 2022 07:41 AM

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Given a relational schema r(A, B, C, D), does A BC logically imply A B

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Given a relation r ABCD A BC means attributes B and ...View the full answer

Database System Concepts

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