Given relations r(w, x) and s(y, z), the result of select distinct w, x from r, s is guaranteed to be same as r, provided

r has no duplicates and s is non-empty

s has no duplicates and r is non-empty

r and s have the same number of tuples

Given relations r(w, x) and s(y, z), the result of select distinct w,

1.	Given relations r(w, x) and s(y, z), the result of select distinct w, x from r, s is guaranteed to be same as r, provided
A.	r has no duplicates and s is non-empty
B.	r and s have no duplicates
C.	s has no duplicates and r is non-empty
D.	r and s have the same number of tuples
Answer» B. r and s have no duplicates

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Given relations r(w, x) and s(y, z), the result of select distinct w, x from r, s is guaranteed to be same as r, provided

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