Suppose that a dirty page in the cache has been written by two active transactions and that one of the transactions commits. Describe howthe caching procedure works in this case.

Question

What will be an ideal response?

Answer 1

The write-ahead feature implies that the page cannot be written until the update records of both transactions have been stored in the log. Assuming update records contain after-images, the page does not have to be written out except as dictated by the rule relating to the use of checkpoint records.