Question

Let R(A, B, C, D) be a relation whose schema satisfies the set of functional dependencies ? AB ? C ? C ? D ? D ? A • (10 points) Find all subsets of the schema of R and compute closures for all non-empty subsets of R. • (10 points) Identify all non-trivial functional dependencies and list all keys (Hint: there are exactly 3 keys) • (5 points) List all BCNF violations. • (20 points) Decompose R, as necessary into collections of relations that are in BCNF.

          Let R(A, B, C, D) be a relation whose schema satisfies the set of functional dependencies
? AB ? C
? C ? D
? D ? A
• (10 points) Find all subsets of the schema of R and compute closures for all non-empty
subsets of R.
• (10 points) Identify all non-trivial functional dependencies and list all keys (Hint: there are
exactly 3 keys)
• (5 points) List all BCNF violations.
• (20 points) Decompose R, as necessary into collections of relations that are in BCNF.

Let R(A, B, C, D) be a relation whose schema satisfies the set of functional dependencies
? AB ? C
? C ? D
? D ? A
• (10 points) Find all subsets of the schema of R and compute closures for all non-empty
subsets of R.
• (10 points) Identify all non-trivial functional dependencies and list all keys (Hint: there are
exactly 3 keys)
• (5 points) List all BCNF violations.
• (20 points) Decompose R, as necessary into collections of relations that are in BCNF.

Added by Miguel G.

Computer Science and Information Technology

Trishna Knowledge Systems 2018 Edition

Instant Answer

Solved by Expert Fatina Seck

Step 1

Finding all subsets of the schema of R and computing closures: - Subset {A}: Closure = {A} - Subset {B}: Closure = {B} - Subset {C}: Closure = {C} - Subset {D}: Closure = {D} - Subset {A,B}: Closure = {A,B,C,D} - Subset {A,C}: Closure = {A,B,C,D} - Subset {A,D}: Show more…

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Let R(A,B,C,D) be a relation whose schema satisfies the set of functional dependencies: ABC CD DA (10 points) Find all subsets of the schema of R and compute closures for all non-empty subsets of R. (10 points) Identify all non-trivial functional dependencies and list all keys (Hint: there are exactly 3 keys). (5 points) List all BCNF violations. (20 points) Decompose R, as necessary, into collections of relations that are in BCNF.