DBMS · Question 9 · Medium
What does the basic Two-Phase Locking (2PL) protocol guarantee?
- Freedom from deadlock
- Cascadeless schedules
- Freedom from starvation
- Conflict serializability
Answer and explanation
Answer: D. Conflict serializability
Explanation: Basic 2PL (a growing phase followed by a shrinking phase) guarantees conflict-serializable schedules. It does not prevent deadlocks, and only the strict variant avoids cascading rollbacks.
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