Sql server® 2012 t-sql fundamentals

  

211

C H A P T E R   7

Beyond the Fundamentals of 

Querying

T

his chapter starts with the profound window functions, which allow you to apply calculations 

against sets in a flexible and efficient manner. The chapter then proceeds with techniques for piv-

oting and unpivoting data. Pivoting means rotating data from a state of rows to a state of columns. 

Unpivoting means rotating data from a state of columns to a state of rows. The chapter then finishes 

with a discussion of grouping sets. Grouping sets are sets of attributes by which data can be grouped. 

This chapter covers techniques for requesting multiple grouping sets in the same query.

Note that all subjects covered in this chapter may be considered advanced for readers who are 

new to T-SQL; therefore, the chapter is optional reading. If you already feel comfortable with the ma-

terial discussed in the book so far, you may want to tackle this chapter; otherwise, feel free to skip it at 

this point and return to it later after you’ve gained more experience.