SQL Server implements three different physical operators to perform joins. In this session, we will examine how each of these operators works, including its advantages and challenges. Using real life examples, we will better understand the logic behind the optimizer’s decisions on which operator to use for various joins. Finally, we will learn how to avoid some common join related pitfalls and how to get better performance from our queries.

In this session, we revisit some of the fundamental design principals of relational databases—normalization rules, key selection, and the controversies associated with these issues—from a very hands-on, practical perspective. We also consider the benefits and challenges of using different types of keys (natural, surrogates, artificial, others) from multiple aspects, including data consistency, application development, maintenance, portability, and performance.