The __________ requires that each transaction Ti executes in two or three different phases in its lifetime, depending on whether it is a read-only or an update transaction.
A. Validation protocol
B. Validation-based protocol
C. Timestamp protocol
D. Timestamp-ordering protocol
Answer:A
The __________ requires that each transaction Ti executes in two or three different phases in its lifetime, depending on whether it is a read-only or an update transaction.
A. Validation protocol B. Validation-based protocol C. Timestamp protocol D. Timestamp-ordering protocol
Explanation: A concurrency-control scheme imposes overhead of code execution and possible delay of transactions. It may be better to use an alternative scheme that imposes less overhead.