Explain why the write-ahead feature of a write-ahead log is needed.
What will be an ideal response?
The write-ahead feature of a write-ahead log means the update record is appended to the log before the database is updated.
Suppose that the database is updated before the update record is appended to the log. If the system should crash between the update and the log entry, the recovery process has no way of rolling the transaction back. If, on the other hand, the update record is appended first, this problem is avoided.
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Indicate whether the statement is true or false
Once workbook sharing is removed, the contents of the tracking log are _______, and there is no way to retrieve the history of edits made to the document.
A. saved B. copied C. erased D. backed up