When has no common attributes then value of ((R⋈S)÷S)) is
When R, S has no common attributes then value of ((R⋈S)÷S)) is always equal to
- A.
S
- B.
R x S
- C.
R ⋈ S
- D.
None
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Correct answer: D
The division operation (R⋈S)÷S can be understood as finding those tuples in R that, when combined with all tuples in S, produce tuples that are present in R⋈S.
Since R and S have no common attributes, the result of R⋈S is the Cartesian product R×S.
So,(R⋈S)÷S simplifies to finding all tuples in R such that for every tuple in S, the combination is in R×S, which trivially holds for all tuples in R.
Thus, the result is all tuples in R.
Therefore, the value of (R⋈S)÷S is: R