Gce Model Questions Vol1 2025 Computer Studies Question 4

Consider a relation \(R(A,B,C,D,E)\) with the functional dependencies: \(A \rightarrow B\) \(A \rightarrow C\) \(C \rightarrow D\) \(BC \rightarrow E\) a) Determine the highest normal form of \(R\). b) Decompose \(R\) into a set of relations that are in Boyce‑Codd Normal Form (BCNF). c) Write an SQL query that returns all values of \(A\) for which the corresponding \(D\) is greater than 5000 and the corresponding \(E\) is less than 2000. Assume the BCNF relations are stored as tables \(R1(C,D)\), \(R3(B,C,E)\) and \(R4(A,B,C)\). d) Given the following data in the three tables: \(R1\): \((C=1,D=6000), (C=2,D=4000), (C=3,D=8000), (C=4,D=3000)\) \(R3\): \((B=10,C=1,E=1500), (B=11,C=2,E=2500), (B=12,C=3,E=1800), (B=13,C=4,E=2100)\) \(R4\): \((A=100,B=10,C=1), (A=101,B=11,C=2), (A=102,B=12,C=3), (A=103,B=13,C=4)\) How many rows will the query return?