Choose a set of transactions for an application of your choice (other than a banking or student registration system). For each isolation level weaker than SERIALIZABLE, give an example of a schedule that produces an erroneous situation.

What will be an ideal response?



Airline reservation system:
REPEATABLE READ
(SELECT and print list : passengers on flight 100)1
(Make newreservation on flight 100)2
(Read and print item : number of passengers on flight 100)1
Printout is inconsistent
READ COMMITTED
(read : seat 5B is empty)1
(read : seat 5B is empty)2 (reserve seat 5B for passenger 10)2 commit2
((reserve seat 5B for passenger 127)1
Seat 5B is reserved for two passengers.
READ UNCOMMITTED
(write request item : passenger requests exotic meal for seat 5B)1
(read request item; write order item : order meal from caterer )2 commit2
abort1

Meal has been ordered that passenger does not want.

Computer Science & Information Technology

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Indicate whether the statement is true or false

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A) knowledge base B) Web crawler C) page ranker D) sponsored link

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a. true b. false

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a. true b. false

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