26 an phase in a two phase lock is when a transaction

This preview shows page 140 - 144 out of 209 pages.

26.A(n) ____ phase in a two-phase lock is when a transaction releases all locks andcannot obtain any new lock.a.growingc.lockingb.shrinkingd.unlockingANS:BPTS:1REF:45327.A(n) ____ condition occurs when two or more transactions wait for each other tounlock data.a.deadlockc.binary lockb.exclusive lockd.two-phase lockANS:APTS:1REF:45328.The ____ approach to scheduling concurrent transactions assigns a global uniquestamp to each transaction.a.scheduledc.uniqueb.table-lockingd.timestampingANS:DPTS:1REF:45529.In the optimistic approach, during the ____ phase, a transaction scans the database,executes the needed computations, and makes the updates to a private copy of thedatabase values.a.readc.writeb.validationd.shared
ANS:APTS:1REF:45730.In the optimistic approach, during the ____ phase, changes are permanentlyapplied to the database.a.readc.writeb.validationd.sharedANS:CPTS:1REF:457COMPLETION1.Although the DBMS is designed to recover a database to a previous consistentstate (when an interruption prevents the completion of a required set oftransactions), the transactions themselves are defined by the end user orprogrammer and must be ____________________ correct.ANS:semanticallyPTS: 1REF: 4402.If a(n) ____________________ is issued before the termination of a transaction,the DBMS will restore the database only for that particular transaction, rather thanfor all transactions, in order to maintain the durability of the previous transactions.ANS:ROLLBACKPTS: 1REF: 4433.The objective of ____________________ control is to ensure the serializability oftransactions in a multiuser database environment.ANS:concurrencyPTS: 1REF: 443
4.____________________ control is important because the simultaneous executionof transactions over a shared database can create several data integrity andconsistency problems.ANS:ConcurrencyPTS: 1REF: 443-4445.The ____________________ interleaves the execution of database operations toensure serializability.ANS:schedulerPTS: 1REF: 4476.To determine the appropriate order of the operations, the scheduler bases its actionson concurrency control algorithms, such as ____________________ or timestamping methods.ANS:lockingPTS: 1REF: 4477.Most multiuser ______________________________ automatically initiate andenforce locking procedures, where all locking information is managed by the lockmanager.ANS:DBMSsdatabase management systemsdatabase management systems (DBMSs)PTS: 1REF: 4488.____________________ can take place at any of the following levels: database,table, page, row, or field.ANS:LockingPTS: 1REF: 449
9.____________________-level locks are less restrictive than database-level locks,but they create traffic jams when many transactions are waiting to access the sametable.ANS:TablePTS: 1REF: 45010.As a rule, a(n) ____________________ must unlock the object after itstermination.ANS:transactionPTS: 1REF: 45211.The ____________________ rule states that only one transaction at a time canown an exclusive lock on the same object.

Upload your study docs or become a

Course Hero member to access this document

Upload your study docs or become a

Course Hero member to access this document

End of preview. Want to read all 209 pages?

Upload your study docs or become a

Course Hero member to access this document

Term
Spring
Professor
KITTEN
Tags
Relational model

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture