Suppose we have a relation schema R(A, B, C) with FD A → B. Suppose also that we decide to decompose this schema into S(A, B) and T(B, C). Give an example of an instance of relation R whose projection onto S and T and subsequent rejoining does not yield the same relation instance.

Suppose we have a relation schema R(A, B, C) with FD A → B. Suppose also that we decide to decompose this schema into S(A, B) and T(B, C). Give an example of an instance of relation R whose projection onto S and T and subsequent rejoining does not yield the same relation instance.

Computer Networking: A Top-Down Approach (7th Edition)

7th Edition

ISBN:9780133594140

Author:James Kurose, Keith Ross

Publisher:James Kurose, Keith Ross

Chapter1: Computer Networks And The Internet

Section: Chapter Questions

Problem R1RQ: What is the difference between a host and an end system? List several different types of end...

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Question

Suppose we have a relation schema R(A, B, C) with FD A → B. Suppose also
that we decide to decompose this schema into S(A, B) and T(B, C). Give an example of
an instance of relation R whose projection onto S and T and subsequent rejoining does not
yield the same relation instance.

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