Question

5.2 Which of the following scenarios may lead to an
irrecoverable error in a database system?
(a) A transaction writes a data item after it is
read by an uncommitted transaction
(b) A transaction reads a data item after it is
read by an uncommitted transaction
(c) A transaction reads a data item after it is
written by a committed transaction
(d) A transaction reads a data item after it is
written by an uncommitted transaction​

Answer 1

Answer:

option D is the answer...

Explanation:

Option C is a normal operation.

Option B is also fine as no write operation is involved.

Option A can be recovered, but option D can’t be.