Q. Which of the following fields does the update log record have?

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Q. The unique identifier of the transaction that performed the write operation is called as _______

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Q. The value of the data item prior to the write is called as _________

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Q. If a transaction does not modify the database until it has committed it is said to use a _______ modification technique

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Q. We say that a transaction has been ________ when its commit log record has been output to stable storage.

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Q. State true or false: Using checkpoints reduces overhead

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Q. A __________ checkpoint is a checkpoint where transactions are allowed to perform updates even while buffer blocks are being written out.

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Q. If the database modifications occur while the transaction is still active, the transaction is said to use the __________ modification technique

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Q. The log is a sequence of _________ recording all the update activities in the database.

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Q. The current copy of the database is identified by a pointer, called ____________ which is stored on disk.

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Q. A special redo-only log record <Ti , Xj , V1> is written to the log, where V1 is the value being restored to data item Xj during the rollback. These log records are sometimes called

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Q. In order to reduce the overhead in retrieving the records from the storage space we use

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Q. The order of log records in the stable storage ____________ as the order in which they were written to the log buffer.

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Q. Before a block of data in main memory can be output to the database, all log records pertaining to data in that block must have been output to stable storage. This is

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Q. Writing the buffered log to __________ is sometimes referred to as a log force.

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Q. The _______________ policy, allows a transaction to commit even if it has modified some blocks that have not yet been written back to disk.

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Q. ______________ policy allows multiple updates to accumulate on a block before it is output to stable storage, which can reduce the number of output operations greatly for frequently updated blocks.

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Q. The ___________ policy, allows the system to write modified blocks to disk even if the transactions thatmade those modifications have not all committed.

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Q. Locks on buffer blocks are unrelated to locks used for concurrency-control of transactions, and releasing them in a non-two-phase manner does not have any implications on transaction serializability. This is

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Q. The __________________ contains a list of blocks that have been updated in the database buffer.

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