Question

Which one is true about clustered index?

(a) Clustered index is not associated with table

(b) Clustered index is built by default on unique key columns

(c) Clustered index is not built on unique key columns

(d) None of the mentioned

The question was posed to me in quiz.

Question is taken from Index Definition in SQL topic in division Indexing and Hashing of Database Management

Answer 1

The correct answer is (b) Clustered index is built by default on unique key columns

The best explanation: Nonclustered indexes have a structure separate from the data rows. A nonclustered index contains the nonclustered index key values and each key value entry has a pointer to the data row that contains the key value.