Oracle Index Types - Quiz

Each question is worth one point. Select the best answer or answers for each question.

1.	Which of the following are valid Oracle index structures? Please select all the correct answers.
	A.	Hierarchical
	B.	B-tree
	C.	Bitmap
	D.	Byte mapped

2.	Which of the following statements are true about Oracle indexes? Please select all the correct answers.
	A.	An Oracle index can contain only unique values.
	B.	An Oracle index must allow duplicate values.
	C.	An Oracle index can contain either duplicate values or unique values.
	D.	An Oracle index can be ascending, descending or neither.

3.	Why are indexes faster for retrieving data? Please select all the correct answers.
	A.	Indexes are kept on high-speed disks.
	B.	Indexes keep less information, so they require fewer I/O operations.
	C.	Oracle database internals favor index-based retrieval.
	D.	Indexes usually are kept in sorted order, so finding a particular row is faster.