Oracle Database Administration I — Question 11

Which two statements are true about the results of using the INTERSECT operator in compound queries? (Choose two.)

Answer options

• A. Column names in each SELECT in the compound query can be different
• B. The number of columns in each SELECT in the compound query can be different
• C. Reversing the order of the intersected tables can sometimes affect the output
• D. INTERSECT returns rows common to both sides of the compound query
• E. INTERSECT ignores NULLs

Correct answer: A, D

Explanation

The correct answer includes A and D because the INTERSECT operator allows for different column names as long as the data types match, and it returns only the rows that are common in both queries. Option B is incorrect since the number of columns must be the same for the INTERSECT operation to work, while option C is incorrect as reversing the order of the tables does not affect the output of the INTERSECT operator.