Exam 10: Transaction Management and Concurrency Control

In a page-level lock,the DBMS will lock an entire diskpage.

Most multiuser automatically initiate and enforce locking procedures,where all locking information is managed by the lock manager.

To determine the appropriate order of the operations,the scheduler bases its actions on concurrency control algorithms,such as or time stamping methods.

A diskpage,or page,is the equivalent of a .

In the wait/die scheme,:

Serializability means that data used during the execution of a transaction cannot be used by a second transaction until the first one is completed.

A growing phase in a two-phase lock is when a transaction acquires all the required locks without locking any data.

The last step in the write-through technique recovery procedure is to identify the last checkpoint in the transaction log.

A(n)lock exists when concurrent transactions are granted read access on the basis of a common lock.

In the optimistic approach,during the phase,changes are permanently applied to the database. a.read b.validation c.write d.shared

A(n)specifically reserves access to the transaction that locked the object.

The scheduler's main job is to create a(n)of a transaction's operation,in which the interleaved executions of transactions yield the same results as if the transactions were executed in serial order.

A(n)phase in a two-phase lock is when a transaction releases all locks and cannot obtain any new lock.

A lock guarantees the open use of a data item to multiple transactions.

The phenomenon of uncommitted data occurs when two transactions are executed concurrently and the first transaction is rolled back after the second transaction has already accessed the uncommitted data-thus violating the isolation property of transactions.

are required to prevent another transaction from reading inconsistent data.

One of the three most common data integrity and consistency problems is .

-level locks are less restrictive than database-level locks,but they create traffic jams when many transactions are waiting to access the same table.

ANSI defines four events that signal the end of a transaction.Of the following events,which is defined by ANSI as being equivalent to a COMMIT?

What is a rule that applies to the two-phase locking protocol?