Consider two relations R1 (A,B) with the tuples(1, 5), (3, 7) and R2 (A, C) = (1, 7), (4, 9). Assume that R(A,B,C) is the full natural outer join of R1 and R2 . Consider the following tuples of the form (A, B, C): a = (1, 5, null), b = (1, null, 7), c = (3, null, 9), d = (4, 7, null), e = (1, 5, 7), f = (3, 7, null), g = (4, null, 9). Which one of the following statements is correct?

R contains a, b, e, f, g but not c, d.

R contains all of a, b, c, d, e, f, g.

R contains e, f, g but not a, b.

Consider two relations R1 (A,B) with the tuples(1, 5), (3, 7) and R2 (

1.	Consider two relations R₁ (A,B) with the tuples(1, 5), (3, 7) and R₂ (A, C) = (1, 7), (4, 9). Assume that R(A,B,C) is the full natural outer join of R₁ and R₂ . Consider the following tuples of the form (A, B, C): a = (1, 5, null), b = (1, null, 7), c = (3, null, 9), d = (4, 7, null), e = (1, 5, 7), f = (3, 7, null), g = (4, null, 9). Which one of the following statements is correct?
A.	R contains a, b, e, f, g but not c, d.
B.	R contains all of a, b, c, d, e, f, g.
C.	R contains e, f, g but not a, b.
D.	R contains e but not f, g.
Answer» D. R contains e but not f, g.

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