Beginning T-SQL with Microsoft® SQL Server® 2005 and 2008

Chapter 8. Multi-Table Queries

At the beginning of this book, we briefly discussed some of the concepts of database design. You'llrecall that information is often broken down into pieces and stored in several tables to improve accuracy andreduce redundancy. This leaves you with one of the greatest challenges in relational database work—putting the information back together.

In this chapter, you learn about

• Combining columns from multiple tables using subqueries and joins

• Using legacy and ANSI standard join syntax applied in the FROM and WHERE clauses

• The difference between inner, outer, full, and cross joins

• Applying the UNION operator to combine parallel result sets

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