Give an example of a schedule in which a pessimistic concurrency control makes a transaction wait but later allows it to commit, while an optimistic concurrency control restarts the transaction.
What will be an ideal response?
r2(y) w1(x) r2(x) commit1 request to commit2
A pessimistic control would force T2 to w ait w hen it requested to read x but would
then allowthe operation after T1 commits and subsequently allow T2 to commit. An
optimistic control would abort T2 when it requested to commit.
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If the sort pattern split routine consistently splits the array into two pieces size 1 and another of size N-1 then the run time is”
a) O(N 2 ) b) O(log N) c) O(N 1/2 ) d) O(N log N) e) The run-time depends on too many things to answer this.
A __________ is when a port intentionally drops a well-formed frame.
A. failure B. halt C. drop D. discard
Each variable in an array has the same name and data type.
Answer the following statement true (T) or false (F)
Which of the following refers to verifying the sender or receiver (or both) is who they claim to be?
A. Authentication B. Nonrepudiation C. Availability D. Authorization