Consider the following statements:
A. A database design is in BCNF if each member of the set of relation schemas that constitutes the design is in BCNF.
B. A BCNF schema can have a transitive dependency.
C. It is always possible to obtain a 3NF design without sacrificing a lossless join.
D. There are multivalued dependencies in 4NF.
Choose the correct answer from the options given below:
Pick an option to check yourself, or open the answer below.
Show answer & explanation
Correct answer: D. A, C and D only
Explanation
A is the definition of a BCNF design. C is true (lossless, dependency-preserving 3NF synthesis always exists). In a 4NF relation the only MVDs are those implied by keys, which the keyed answer counts as D being true. B is false: BCNF rules out transitive dependencies.More Database Management Systems questions
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