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The Real MTCS SQL Server 2008 Exam 70/432 Prep Kit- P128: 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 14 617 When preparing for the exam ensure you have practiced using the CREATE ALTER and DROP DDL statements and have achieved a good understanding of the DDL syntax. The AdventureWorks sample database is a great tool for learning Transact-SQL without the risk of damaging your live databases. Exercises in this chapter are based on the AdventureWorks database. Perform all exercises to get hands-on experience in writing and executing DDL queries. Configuring Implementing. Minimally Logged Operations and the Database Recovery Model Earlier examples in this chapter have made use of INSERT UPDATE and DELETE DML statements. These DML operations as well as the MERGE statement are logged operations. When an operation is logged data about the operation is stored in the SQL Server transaction log. The transaction log files can be backed up and replayed into an earlier database backup. Although the log replay functionality is slow it allows you to restore the database to the point in time when the database file was lost. For performance reasons some operations that affect SQL Server data can be performed as nonlogged or minimally logged. This means that the information about these operations is not fully recorded in the SQL Server transaction log. Nonlogged operations offer much better performance than logged operations. If a nonlogged operation occurs after the database has been backed up you will not be able to replay the logs into the database after you have restored the database from backup. The following DML operations are either nonlogged or minimally logged depending on database recovery model TRUNCATE TABLE. WRITETEXT and UPDATETEXT. These statements are deprecated and should not be used. Use column.Write instead. SELECT INTO. Continuec 618 Chapter 14 Implementing Objects You cannot use these statements when publishing tables as part of replication. The selected database recovery model determines what transactions are recorded in the .
