Q. In timestamp ordering protocol, suppose that the transaction Ti issues write(Q) and TS(Ti)<W-timestamp(Q), then

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Q. The _________ requires each transaction executes in two or three different phases in its lifetime

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Q. During __________ phase, the system reads data and stores them in variables local to the transaction.

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Q. During the _________ phase the validation test is applied to the transaction

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Q. During the _______ phase, the local variables that hold the write operations are copied to the database

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Q. Read only operations omit the _______ phase

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Q. Which of the following timestamp is used to record the time at which the transaction started execution?

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Q. Which of the following timestamps is used to record the time when a transaction has finished its read phase?

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Q. Which of the following timestamps is used to record the time when a database has completed its write operation?

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Q. State true or false: Locking and timestamp ordering force a wait or rollback whenever a conflict is detected.

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Q. State true or false: We determine the serializability order of validation protocol by the validation ordering technique

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Q. In _______ schemes, each write operation creates a new version of Q

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Q. If the first update is overwritten by a second, it is called as a _______ update

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Q. State true or false: Snapshot isolation prevents lost updates

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Q. Which of the following is a variant of snapshot isolation

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Q. Under ________ the system uses locking mechanism that applies only to updates

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Q. The situation in which each pair of transactions has read a data written by the other, but there is no data written by the transactions is called as _______

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Q. Oracle uses __________ for the serializable isolation level

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Q. State true or false: Snapshot isolation has low overhead

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Q. In ________ no two aborts occur unless two concurrent transactions update the same data item.

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