Filters
Question type

Study Flashcards

The scheduler establishes the order in which the operations within concurrent transactions are executed.

A) True
B) False

Correct Answer

verifed

verified

A field-level lock allows concurrent transactions to access the same row,as long as they require the use of different fields within that row.

A) True
B) False

Correct Answer

verifed

verified

What are database checkpoints?

Correct Answer

verifed

verified

Database checkpoints are operations in w...

View Answer

A ____ lock allows concurrent transactions to access different rows of the same table.


A) database-level
B) table-level
C) page-level
D) row-level

E) A) and D)
F) A) and C)

Correct Answer

verifed

verified

Durability requires that all portions of the transaction must be treated as a single,logical unit of work in which all operations are applied and completed to produce a consistent database.

A) True
B) False

Correct Answer

verifed

verified

Uniqueness ensures that no equal time stamp values can exist,and ____________________ ensures that time stamp values always increase.

Correct Answer

verifed

verified

The multiuser DBMS must implement controls to ensure serializability and isolation of transactions,in addition to atomicity and durability,in order to guard the database's consistency and integrity.

A) True
B) False

Correct Answer

verifed

verified

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

A) True
B) False

Correct Answer

verifed

verified

When using an optimistic approach,during the write phase,the transaction is validated to ensure that the changes made will not affect the integrity and consistency of the database.

A) True
B) False

Correct Answer

verifed

verified

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

Correct Answer

verifed

verified

DBMSs
database manag...

View Answer

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) True
B) False

Correct Answer

verifed

verified

An optimistic approach is based on the assumption that the majority of the database operations do not conflict.

A) True
B) False

Correct Answer

verifed

verified

As a rule,a(n)____________________ must unlock the object after its termination.

Correct Answer

verifed

verified

How does a shared/exclusive lock schema increase the lock manager's overhead?

Correct Answer

verifed

verified

The type of lock held must be known befo...

View Answer

A(n) ____ lock has only two stages (0 and 1) .


A) shared
B) exclusive
C) binary
D) two-phase

E) A) and D)
F) All of the above

Correct Answer

verifed

verified

The ____________________ rule states that only one transaction at a time can own an exclusive lock on the same object.

Correct Answer

verifed

verified

The ANSI has defined standards that govern SQL database transactions.Transaction support is provided by two SQL statements: ____ and ROLLBACK.


A) RETRIEVE
B) ASSIGN
C) UPDATE
D) COMMIT

E) A) and B)
F) A) and C)

Correct Answer

verifed

verified

In the optimistic approach,during the ____ phase,changes are permanently applied to the database.


A) read
B) validation
C) write
D) shared

E) None of the above
F) A) and B)

Correct Answer

verifed

verified

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

A) True
B) False

Correct Answer

verifed

verified

Database transaction ____________________ restores a database from an inconsistent state to a previously consistent state.

Correct Answer

verifed

verified

Showing 21 - 40 of 70

Related Exams

Show Answer