TAILIEUCHUNG - The Real MTCS SQL Server 2008 Exam 70/432 Prep Kit- P134

The Real MTCS SQL Server 2008 Exam 70/432 Prep Kit- P134: 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. | Implementing Objects Chapter 14 647 Working with Tables Indexes and Constraints 0 Use the CREATE TABLE statement to define a table by listing columns in the table along with corresponding data types. 0 Indexes are useful for fast searching and sorting data. One clustered index is allowed per table and the underlying table data is stored in the order of the clustered index. Nonclustered indexes are separate lookup structures that point to the table heap or the clustered index. 0 Full-text indexes are used for specialized querying using functions like FREETEXT. Only one full-text index is allowed per table. 0 Indexes and constraints can be defined separately and are bound to an existing table. Viewing and Modifying Data 0 A view is a SELECT statement saved with a name. A view can be updated if it is based on a single table or if it has INSTEAD OF triggers defined on it. Indexes can be created on a view as well as on a table. 0 A stored procedure is any Transact-SQL statement saved with a name. Stored procedures can update data by using DML statements. 0 A function is a Transact-SQL statement that usually performs a calculation. Functions must return a value. Functions that return a single value are known as scalar functions whereas functions that return a table-valued expression are known as table-valued functions. 0 A trigger is a statement that runs automatically when data in a particular table or view is modified. Triggers can cancel transactions by using the ROLLBACK TRANSACTION statement. Triggers can be specified as FOR AFTER or INSTEAD OF. You can access special INSERTED and DELETED tables within the trigger to find out the old and new values of rows that are being updated. 648 Chapter 14 Implementing Objects Exam Objectives Frequently Asked Questions Q When should I use the TRUNCATE TABLE statement rather than the DELETE statement A You should use the TRUNCATE TABLE statement if you want to quickly and indiscriminately empty the table. A performance advantage

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