Chapter 10 Transaction Management and Concurrency Control

Discussion Focus Why does a multi-user database environment give us a special interest in transaction management and concurrency control? Begin by exploring what a transaction is, what its components are, and why it must be managed carefully even in a single-user database environment. Then explain why a multi-user database environment makes transaction management even more critical. Emphasize the following points:  A transaction represents a real-world event such as the sale of a product.  A transaction must be a logical unit of work. That is, no portion of a transaction stands by itself. For example, the product sale has an effect on inventory and, if it is a credit sale, it has an effect on customer balances.  A transaction must take a database from one consistent state to another. Therefore, all parts of a transaction must be executed or the transaction must be aborted. (A consistent state of the database is one in which all data integrity constraints are satisfied.)