Consider the following log sequence of two transactions on a bank account, with initial balance 12000, that transfer 2000 to a mortagage payment and then apply a 5% interest.

We need not redo log records 2 and 3 because transaction T1 has committed

We must redo log record 6 to set B to 10500

We must redo log record 6 to set B to 10000 and the redo log records 2 and 3.

We need not redo log records 2 and 3 because transaction T1 has committed

We can apply redo and undo operations in arbitrary order because they are idempotent

Consider the following log sequence of two transactions on a bank acco

1.	Consider the following log sequence of two transactions on a bank account, with initial balance 12000, that transfer 2000 to a mortagage payment and then apply a 5% interest.
A.	We must redo log record 6 to set B to 10500
B.	We must redo log record 6 to set B to 10000 and the redo log records 2 and 3.
C.	We need not redo log records 2 and 3 because transaction T1 has committed
D.	We can apply redo and undo operations in arbitrary order because they are idempotent
Answer» C. We need not redo log records 2 and 3 because transaction T1 has committed

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Consider the following log sequence of two transactions on a bank account, with initial balance 12000, that transfer 2000 to a mortagage payment and then apply a 5% interest.

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