DBMS · Question 8 · Medium
DBMS question 8
Transaction T1 reads a row, then transaction T2 updates that row and commits, and then T1 reads the same row again and gets a different value. This anomaly is called a:
- Dirty read
- Phantom read
- Lost update
- Non-repeatable read
Answer and explanation
Answer: D. Non-repeatable read
Explanation: Reading the same row twice and getting different committed values is a non-repeatable read. A dirty read involves uncommitted data; a phantom read involves new rows matching a condition.
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