Review Questions
- What are the ACID properties? Define atomicity, consistency, isolation, and durability and illustrate them through examples.
- Define the terms transaction, schedule, complete schedule, and serial schedule.
- Why does a DBMS interleave concurrent transactions?
- When do two actions on the same data object conflict? Define the anomalies that can be caused by conflicting actions (dirty reads, unrepeatable reads, lost updates).
- What is aserializable schedule? What is a recoverable schedule? What is a schedule that avoid cascading aborts? What is a strict schedule?
- What is a locking protocol? Describe the Strict Tow-Phase Locking (Strict 2PL) protocol. What can you say about the schedules allowed by this protocol?
- What overheads are associated with lock-based concurrency control? Discuss blocking and a
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