a. How does releasing all locks at the end of the transaction relate to two-phase locking?
b. In general, how should the boundaries of a transaction be defined?
c. What is deadlock? How can it be avoided? How can it be resolved once it occurs?
d. Explain the difference between optimistic and pessimistic locking.
e. Explain the benefits of marking transaction boundaries, declaring lock characteristics, and letting the DBMS place locks.