Which of the following is true ? I. Implementation of self-join is possible in SQL with table alias. II. Outer-join operation is basic operation in relational algebra. III. Natural join and outer join operations are equivalent. (A) I and II are correct. (B) II and III are correct. (C) Only III is correct. (D) Only I is correct.

Which of the following is true ?

I. Implementation of self-join is possible in SQL with table alias.

II. Outer-join operation is basic operation in relational algebra.

III. Natural join and outer join operations are equivalent.

(A) I and II are correct. (B) II and III are correct.

(C) Only III is correct. (D) Only I is correct.
by

1 Answer

Answer :

(D) Only I is correct.
by

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