CREATE INDEX emp_dept_id_idx ON employee(dept_id); Which of the following statements are true with respect to the above index?
Answer options
A
May reduce the amount of disk I/O for SELECT statements.
B
Stores an index in the EMPLOYEE table.
C
Increases the chance of full table scans.
D
Overrides the unique index.
Correct answer: May reduce the amount of disk I/O for SELECT statements.
Explanation
Quick AnswerThe correct answer is May reduce the amount of disk I/O for SELECT statements. because it directly addresses the core logic of Database Management.
An index on dept_id speeds up SELECT queries filtering by that column by reducing disk I/O.