Given below are two statements: Which of the following concurrency control protocol ensures both conflict serializability and freedom from deadlock?
Statement I: Two phase locking
Statement II: Timestamp ordering In the light of the above statements, choose the most appropriate answer from the options given below:
Pick an option to check yourself, or open the answer below.
Show answer & explanation
Correct answer: D. Statement I is incorrect but Statement II is correct
Explanation
Two-phase locking guarantees conflict serializability but can deadlock. Basic timestamp ordering guarantees conflict serializability and never waits, so it is deadlock-free.
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