Julia has a shared lock on the savings account and Bill is trying to perform an action requesting an exclusive lock on the same data:
A) Bill's transaction is granted permission to perform the desired action and Julia's transaction must now wait
B) Bill's transaction must wait until Julia's lock is released
C) Bill's transaction must wait until Julia has read the savings account value
D) None of the above

Question

Quizplus · Accepted Answer

When a shared lock is already acquired on a piece of data, any request for an exclusive lock on the same data must wait until the shared lock is released. This ensures that the shared data remains consistent and is not accessed concurrently by different transactions. Therefore, Bill's transaction must wait until Julia's lock is released before it can request an exclusive lock on the savings account.

Julia Has a Shared Lock on the Savings Account and Bill