If a relation with a Schema R is decomposed into two relations R1 and R2 such that (R1ᴗR2)=R1 then which one of the following is to be satisfied for a lossless joint decomposition (→ indicates functional dependency)
A. (R1∩R2)→R1 or R1∩R2→R2
B. R1∩R2→R1
C. R1∩R2→R2
D. R1∩R2→R1 and R1∩R2→R2
Answer:A
If a relation with a Schema R is decomposed into two relations R1 and R2 such that (R1ᴗR2)=R1 then which one of the following is to be satisfied for a lossless joint decomposition (→ indicates functional dependency)
A. (R1∩R2)→R1 or R1∩R2→R2 B. R1∩R2→R1 C. R1∩R2→R2 D. R1∩R2→R1 and R1∩R2→R2
Explanation: Let R be a relation schema.