The second step of the sharp checkpoint recovery procedure is as follows: The log is scanned forward from the checkpoint. The after-images in all update records are used to update the corresponding items in the database. Assuming a locking concurrency control in which locks are held until commit time, show that the updates can be performed in either of the following orders:
a. As each update record is encountered in the forward scan, the corresponding database update is performed (even though the update records for different transactions are interleaved in the log).
b. During the forward scan, the update records for each transaction are saved in volatile memory, and the database updates for each transaction are all done at once when the commit record for that transaction is encountered during the forward scan.
a. Because that is the order in which the operations took place.
b. Because the transactions can be serialized in commit order
You might also like to view...
The ________ action allows the user to bypass all the prompts that accompany various actions in a database, such as running an update query and importing data into a table
A) SetWarnings B) AutoExec C) GoToControl D) SelectObject
Whenever a more sophisticated loop is called for, such as one that counts backward, it is best to create your own version of a count-controlled loop with a FOR instruction.
Answer the following statement true (T) or false (F)