Database Systems: Design, Implementation, & Management
11th Edition
ISBN: 9781285196145
Author: Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos Coronel
Publisher: Cengage Learning
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Chapter 10, Problem 10P
Program Plan Intro
Pessimistic locking:
It is one of the locking methods in concurrency control. The lock exists in the transaction until the transaction gets committed or rolled back.
Two-phase locking protocol:
It defined the serializability of the transaction but not prevent deadlocks. The process of locking and unlocking can be done using two phases in this protocol. They are: Growing phase and shrinking phase.
Growing phase:
New lock can be occurred on the transaction without unlocking the data items. The data items are locked in this phase.
Shrinking phase:
This phase used to release all transaction but not provide new lock on the transaction.
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What does it mean for a database to be in a stable state? While the database management system may give a symbolic meaning for a transaction, there is no assurance that it faithfully captures the underlying real-world event. What consequences may be expected if this ban were implemented? Explain your point using an illustration. Should we take at face value the apparent meaning of the phrase "serializable transactions"?
An answer to this question: What does it mean to have a stable database state? There is no guarantee that the transaction's symbolic meaning accurately represents the underlying real-world event provided by the database management system. What would be the ramifications of such a prohibition? Using a specific example, explain what you mean. Does the term "serializable transactions" really mean what it appears to?
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Chapter 10 Solutions
Database Systems: Design, Implementation, & Management
Ch. 10 - Prob. 1RQCh. 10 - Prob. 2RQCh. 10 - Prob. 3RQCh. 10 - Prob. 4RQCh. 10 - Prob. 5RQCh. 10 - Prob. 6RQCh. 10 - Prob. 7RQCh. 10 - Prob. 8RQCh. 10 - Prob. 9RQCh. 10 - Prob. 10RQ
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