Oracle Database Administration I — Question 136

Which two statements are true about a self join? (Choose two.)

Answer options

• A. It can be an inner join.
• B. It can be a left outer join.
• C. It must be an equijoin.
• D. The join key column must have an index.
• E. It must be a full outer join.

Correct answer: A, B

Explanation

A self join can indeed be an inner join or a left outer join, making options A and B correct. However, it does not have to be an equijoin (C), the join key column does not necessarily need an index (D), and it is not required to be a full outer join (E).