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The Real MTCS SQL Server 2008 Exam 70/432 Prep Kit- P127

The Real MTCS SQL Server 2008 Exam 70/432 Prep Kit- P127: Congratulations on your journey to become certified in SQL Server 2008. This book will help prepare you for your exam and give you a practical view of working with SQL Server 2008. | 612 Chapter 14 Implementing Objects Introduction SQL Server 2008 is a mature enterprise data platform providing objects for storing accessing and modifying data. In this chapter you will discover how to create tables indexes stored procedures functions and triggers. Designing database objects and writing scripts for their creation is usually the role of database developers. However database administrators must understand the concepts behind database objects and have the skills necessary to create and modify them. This chapter will provide you with these key skills. Database objects are divided into two broad categories storage and programmability. Tables are units of data storage structured by columns and rows. Each column in a table stores data of a specific data type. Many built-in data types are available for you to choose from or you can create custom user-defined data types if necessary. Tables can store large amounts of data which can take a long time to query. To maximize query performance you can create fast lookup structures known as indexes. Indexes are created on frequently searched on columns and enable quick traversal when looking for particular values within a table similar to the index you will find at the end of a printed book. You can associate constraints with table columns. Constraints define the rules to which data in a particular column or columns must adhere. For example you can use a constraint to specify that values stored in the EMailAddress field are of a particular format. Unique constraints ensure that data for a particular column is unique across the table. For example you may enforce that product names are always unique in the Products table. Constraints can also define relationships between tables such as the necessity to have a Customer entity associated with every Order entity. These are known as foreign key constraints. Programmability objects allow you to define Transact-SQL statements that can be reused again and again. Views are