Which of the following states the Rule of Entity Integrity?
a. Every row must have a value for the primary key and each value must be unique.
b. Every foreign key must appear as another table’s primary key.
c. Every row must have a value for the primary key and values may be repeated.
d. None of the above.
A
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The kill-wait concurrency control combines the concepts of the immediate update concurrency control and the timestamp-ordered control. As in the timestamp-ordered system, when a transaction, T1 is initiated, it is assigned a timestamp, TS(T1). However, the system uses the same conflict table as the immediate-update pessimistic control does and resolves conflicts using the rule
If transaction T1 makes a request that conflicts with an operation of active transaction, T2 if TS(T1) < TS(T2), then abort T2, else make T1 wait until T2 terminates. where abort T2 is referred to as a kill because T1 kills T2. a. Showthat the kill-wait control serializes in commit order. b. Give a schedule produced by a kill-wait control that is not serializable in timestamp order. c. Explain why deadlock does not occur in a kill-wait control.
A(n) ____ symbol has its own Timeline.
A. graphic B. movie clip C. button D. icon
Modern network printing requires the use of a print server
a. true b. false
Explain why digital forensics examiners should be most concerned with restrictions applied to customers and security measures.?
What will be an ideal response?