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.

Question

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"?

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Question

Chapter 10, Problem 8P

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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