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Chapter 12
Managing SQL Server Transactions and Locks
SQL Server uses transactions and locks to ensure the consistency and integrity of each database, despite errors that might occur in the system. A transaction is a logical unit of work that consists of a series of statements, such as SELECT or UPDATE statements. Locks prevent conflicts so that users cannot read or modify data that other users are in the process of changing. Transactions use locking to prevent users from modifying data affected by transactions that have not been completed. This chapter introduces you to the fundamentals of transactions and locks and then describes how transactions and locks are used to process data modifications.
To complete the lessons in this chapter, you must have: