Summary

SQL Server is a product widely used by a lot of different people in many different ways. At its core is the relational database engine, and sitting on this foundation are a wealth of features and capabilities. The way that SQL Server databases are designed and administered has changed as the client applications have improved and been integrated into Microsoft's suite of solution development tools. SQL Server is now accessible to business users in addition to technical professionals.

You read about the conceptual, logical, and physical phases of solution design and how they apply to designing a database. A relational database stores data in separate tables, associated through primary key/foreign key relationships that implement the rules of normal form. You saw how flat, spreadsheet-like data is transformed into a normalized structure by applying these rules. Normalizing data structures is not an absolute necessity for all databases and it sometimes is prudent to ignore the rules to simplify the design. Both normalizing and de-normalizing a database design come at a cost that must be carefully considered and kept in balance with the business rules for the solution. These business rules and the user's requirements ultimately drive the capabilities and long-term needs of a project.

You also learned about the client/server database execution model and how SQL Server uses both client-side and server-side components to process requests and to execute queries. The execution and procedure cache allow SQL Server to optimize performance by compiling execution plans for ad-hoc queries and prepared stored procedures.