Database Systems 6th Edition by Ramez Elmasri, Shamkant B. Navathe

Edition 6ISBN: 0136086209

Database Systems 6th Edition by Ramez Elmasri, Shamkant B. Navathe

Edition 6ISBN: 0136086209

Exercise 3

Figure 22.6 -Figure 22.6 shows the log corresponding to a particular schedule at the point of a system crash for the four transactions T<sub>1</sub>(X), T<sub>2</sub>(X), T<sub>3</sub>(X), and T4. Suppose that we use the immediate update protocol with checkpointing. Describe the recovery process from the system crash. Specify which transactions are rolled back, which operations in the log are redone and which (if any) are undone, and whether any cascading rollback takes place.

Figure 22.6
-Figure 22.6 shows the log corresponding to a particular schedule at the point of a system crash for the four transactions T₁(X), T₂(X), T₃(X), and T4. Suppose that we use the immediate update protocol with checkpointing. Describe the recovery process from the system crash. Specify which transactions are rolled back, which operations in the log are redone and which (if any) are undone, and whether any cascading rollback takes place.

Explanation

Verified

First, we note that this schedule is not...