Ôn cuối kỳ DDBMS

What is a distributed database (DDB)?

• A database management software.

• A collection of logically related databases distributed over a computer network.

• A database stored on a single server.

• A collection of unrelated databases.

What is intra-query parallelism?

• Parallelism in executing tasks within the same query.

• Parallelism in executing multiple queries simultaneously.

• Parallelism in the execution of independent tasks.

• Parallelism in the execution of separate operators in the same query.

What is a distributed database management system (D–DBMS)?

• A software that manages a distributed database and provides a distributed access mechanism.

• A distributed database.

• A software that is not related to the database.

• An operating system.

What does a D–DBMS provide to users?

• An access mechanism that makes the distribution of data transparent.

• The ability to store data in a single location.

• The ability to process data centrally.

• Graphics processing capabilities.

What is Pull-only mode in data delivery methods?

• Data is sent based on certain conditions.

• Data is sent from data provider without specific request.

• Data is sent periodically.

• Data is requested from web pages to data provider.

How is Push-only delivery method initiated?

• By conditional request.

• By periodic schedule.

• By request from web pages.

• By event without specific request.

What does Periodic mean by data sending frequency?

• Data is sent irregularly.

• Data is sent on request from web page.

• Data is sent based on certain conditions.

• Data is sent on fixed schedule.

What is Ad-hoc frequency in data delivery methods?

• Sending data to a select group.

• Sending data on special or infrequent request.

• Sending data based on specific conditions.

• Send data on fixed schedule.

How does replication transparency help users?

• Reduces system performance

• Allows users to know the location of all copies of data

• Hides data replication from users

• Increases the number of system errors

What is inter-query parallelism?

• Parallelism in executing multiple queries simultaneously.

• Parallelism in executing separate operators within the same query.

• Parallelism in executing parts of the same query.

• Parallelism in executing independent tasks.