passwella.
Menu

WAEC Data Processing 2017 Question 23

Question 23

Database Management

When a database recovery manager is invoked after a crash, restart proceeds in the following three phases: I. Undo; II. Redo; III. Analysis. Arrange these phases in the right order.

  1. A.I, II, III
  2. B.II, I, III
  3. C.III, II, I
  4. D.I, III, II
Show the answer and explanation

Answer: C (III, II, I)

Explanation

Recovery first analyses the log, then redoes committed work, then undoes unfinished transactions.