Chapter Questions
Explain the role of concurrency control mechanisms in managing serializable execution of concurrent transactions.
Prove that if two-phase policy is violated then it may not be possible to serialize the execution of concurrent transactions.
What is phantom problem? How does it arise? Why does it arise only in dynamic databases? Give a real-life example of phantom problem and develop a scheme to handle it efficiently. Identify the phantom record in your example.
Do you think a lock conversion may give rise to phantom problem? Explain your answer.
Consider developing your own concurrency control mechanism based on dynamic attributes of transactions.