Database System Concepts Sixth Edition Avi Silberschatz Henry F. We provide a set of slides to accompany each chapter. Click on the links below to download the slides in Powerpoint. The slides and figures below are copyright Silberschatz, Korth. Sudarshan, 2005. The slides and figures are authorized for personal use, and for use in conjunction with a course for which Database System Concepts is the prescribed text. Instructors are free to modify. Part 5: Transaction Management. Transactions, ppt. ![]() Page 1 Database System Concepts, 6 th Ed. ©Silberschatz, Korth and Sudarshan See www.db-book.com for conditions on re-use Chapter 14: Transactions Page 2 Database System Concepts, 6 th Ed. ©Silberschatz, Korth and Sudarshan See www.db-book.com for conditions on re-use Chapter 14: Transactions ©Silberschatz, Korth and Sudarshan 14.2 Database System Concepts - 6 th Edition Chapter 14: Transactions? Transaction Concept? Transaction State? Concurrent Executions? Implementation of Isolation? Transaction Definition in SQL? Testing for Serializability. When you perform certain tasks, items bounce to indicate that it's time to use them. All of the various parts of the app's menu are explained well when you first start using My Talking Angela, mini game controls are ultra simple, and the menu icons are large and clear. Talking tom touch jar download. Page 3 Database System Concepts, 6 th Ed. ©Silberschatz, Korth and Sudarshan See www.db-book.com for conditions on re-use Chapter 14: Transactions ©Silberschatz, Korth and Sudarshan 14.2 Database System Concepts - 6 th Edition Chapter 14: Transactions? Transaction Concept? Transaction State? Concurrent Executions? Implementation of Isolation? Transaction Definition in SQL? Testing for Serializability. ©Silberschatz, Korth and Sudarshan 14.3 Database System Concepts - 6 th Edition Transaction Concept? A transaction is a unit of program execution that accesses and possibly updates various data items.? Transaction to transfer $50 from account A to account B: 1. Ny i norge tekstbok. Shopbop Designer Fashion Brands. AmazonGlobal Ship Orders Internationally. A:= A – 50 3. B:= B + 50 6. Two main issues to deal with:? Failures of various kinds, such as hardware failures and system crashes? Concurrent execution of multiple transactions Page 4 Database System Concepts, 6 th Ed. ©Silberschatz, Korth and Sudarshan See www.db-book.com for conditions on re-use Chapter 14: Transactions ©Silberschatz, Korth and Sudarshan 14.2 Database System Concepts - 6 th Edition Chapter 14: Transactions? Transaction Concept? Transaction State? Concurrent Executions? Implementation of Isolation? Transaction Definition in SQL? Testing for Serializability. ©Silberschatz, Korth and Sudarshan 14.3 Database System Concepts - 6 th Edition Transaction Concept? A transaction is a unit of program execution that accesses and possibly updates various data items.? Transaction to transfer $50 from account A to account B: 1. A:= A – 50 3. B:= B + 50 6. Two main issues to deal with:? Failures of various kinds, such as hardware failures and system crashes? Concurrent execution of multiple transactions ©Silberschatz, Korth and Sudarshan 14.4 Database System Concepts - 6 th Edition Example of Fund Transfer? Transaction to transfer $50 from account A to account B: 1. A:= A – 50 3. B:= B + 50 6. Atomicity requirement? If the transaction fails after step 3 and before step 6, money will be “lost” leading to an inconsistent database state? Failure could be due to software or hardware? The system should ensure that updates of a partially executed transaction are not reflected in the database? Durability requirement — once the user has been notified that the transaction has completed (i.e., the transfer of the $50 has taken place), the updates to the database by the transaction must persist even if there are software or hardware failures. Page 5 Database System Concepts, 6 th Ed. ©Silberschatz, Korth and Sudarshan See www.db-book.com for conditions on re-use Chapter 14: Transactions ©Silberschatz, Korth and Sudarshan 14.2 Database System Concepts - 6 th Edition Chapter 14: Transactions? Transaction Concept? Transaction State? Concurrent Executions? Implementation of Isolation? Un venerdi nero suvarile. Transaction Definition in SQL? Testing for Serializability. ©Silberschatz, Korth and Sudarshan 14.3 Database System Concepts - 6 th Edition Transaction Concept? A transaction is a unit of program execution that accesses and possibly updates various data items.? Transaction to transfer $50 from account A to account B: 1. A:= A – 50 3. B:= B + 50 6. Two main issues to deal with:? Failures of various kinds, such as hardware failures and system crashes? Concurrent execution of multiple transactions ©Silberschatz, Korth and Sudarshan 14.4 Database System Concepts - 6 th Edition Example of Fund Transfer? Transaction to transfer $50 from account A to account B: 1. A:= A – 50 3. B:= B + 50 6. Atomicity requirement? If the transaction fails after step 3 and before step 6, money will be “lost” leading to an inconsistent database state? Failure could be due to software or hardware? The system should ensure that updates of a partially executed transaction are not reflected in the database? Durability requirement — once the user has been notified that the transaction has completed (i.e., the transfer of the $50 has taken place), the updates to the database by the transaction must persist even if there are software or hardware failures. ©Silberschatz, Korth and Sudarshan 14.5 Database System Concepts - 6 th Edition Example of Fund Transfer (Cont.)? Transaction to transfer $50 from account A to account B: 1.
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