Views are a powerful database tool that in their simplest form can be used as a low-overhead way to simplify queries or provide column-level or row-level security. They also can be leveraged to mask schema or layout changes in existing applications, and for this reason should be considered during all phases of database design.
Partitioned views can provide a unified view of a table that has been partitioned, or split, to improve performance or accommodate geographically distributed data. The indexed view, new to SQL Server 2000, may have some drawbacks, but can improve performance for certain types of queries.
The next chapter, "Creating and Managing Stored Procedures in SQL Server," discusses one of the most powerful features of SQL Server. Stored procedures allow you to store your T-SQL statements as executable objects in SQL Server, providing administrative and performance benefits including another method of controlling access to data and hiding changes to underlying data structures.