Question

Which of the following guideline is considered during column design?

(a) Keep the length of the index key short for non clustered indexes

(b) An xml data type can only be a key column only in an XML index

(c) Examine column which have composite primary keys

(d) None of the mentioned

I got this question in an internship interview.

My doubt stems from Indexing Strategies topic in division Performance Tuning and Optimization of SQL Server

Answer 1

The correct answer is (b) An xml data type can only be a key column only in an XML index

The explanation is: QL Server 2012 SP1 introduces a new type of XML index known as a Selective XML Index. This new index can improve querying performance over data stored as XML in SQL Server, allow for much faster indexing of large XML data workloads.