Express the query of Exercise 13.19 in Datalog.
What will be an ideal response?
First, we de?ne the transitive closure of DirectFlight:
Flight(?F,?T) :- DirectFlight(?F,?T).
Flight(?F,?T) :- DirectFlight(?F,?I), Flight(?I,?T).
Then we de?ne the required query:
FlightsWithTwoOrMoreStops(?F,?T) :-
DirectFlight(?F,?S1),
DirectFlight(?S1,?S2),
Flight(?S2,?T).
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Explain how an administrator can see a detailed display of the kernel's version number.
What will be an ideal response?
For what is the Atanasoft–Berry Computer best known?
a. It was the first computer to use vacuum tubes instead of mechanical switches. b. It was the first computer to use the binary system. c. It was the first computer to incorporate a magnetic tape system. d. It was the first computer used as a mechanical calculator.
Shill bidding at an auction occurs when a fraudster accepts payment for an item and then fails to deliver it
Indicate whether the statement is true or false.
A data ____ table describes the fields you plan to maintain in a table.
A. structure B. definition C. map D. linked