Question

Which of the following is included in the operational mechanism of the index locking protocol?

(a) Every transaction must have at least one index

(b) A transaction that performs a lookup must acquire a shared lock on all the index leaf nodes that it accesses

(c) The rule of the two phase locking mechanism must be observed

(d) All of the mentioned

I have been asked this question by my school teacher while I was bunking the class.

Origin of the question is Insert, Delete Operations and Predicate Reads in chapter Concurrency Control of RDBMS

Answer 1

Right choice is (d) All of the mentioned

The best explanation: The operational mechanism of the index locking protocol includes, every transaction must have at least one index. A transaction that performs lookup must acquire a shared lock on all the index leaf nodes that it accesses. The rule of the two phase locking mechanism must be followed.