Question 8416 – Transactions

Consider the following partial Schedule S involving two transactions T1 and T2. Only the read and the write operations have been shown. The read operation on data item P is denoted by read(P) and the write operation on data item P is denoted by write(P).

Correct Answer: B

Question 20 Explanation:

T2 is reading the value written by T1 and getting committed before T1 commits. So it is non-recoverable schedule.

T2 must be aborted and then both T1 and T2 must be re-started to ensure transaction atomicity

Schedule S is non-recoverable and cannot ensure transaction atomicity

Only T2 must be aborted and then re-started to ensure transaction atomicity

Schedule S is recoverable and can ensure atomicity and nothing else needs to be done