Questions and answers for exam Preparation

MCQs

Total Questions : 30 | Page 2 of 3 pages

Question 11. A distributed database is which of the following?

A single logical database that is spread to multiple locations and is interconnected by a network
A single logical database that is limited to one location.
A loose collection of file that is spread to multiple locations and is interconnected by a network
A loose collection of file that is limited to one location.

Discuss Question

Answer: Option A. -> A single logical database that is spread to multiple locations and is interconnected by a network

Question 12. Which of the following is not one of the stages in the evolution of distributed DBMS?

Distributed unit of Work
Remote unit of work
Unit of work
Distributed request

Discuss Question

Answer: Option C. -> Unit of work

Question 13. A semijoin is which of the following?

Only the joining attributes are sent from one site to another and then all of the rows are returned.
All of the attributes are sent from one site to another and then only the required rows are returned.
Only the joining attributes are sent from one site to another and then only the required rows are returned.
All of the attributes are sent from one site to another and then only the required rows are returned.

Discuss Question

Answer: Option C. -> Only the joining attributes are sent from one site to another and then only the required rows are returned.

Question 14. A distributed database can use which of the following strategies?

Totally centralized at one location and accessed by many sites
Partially or totally replicated across sites
All of these
Partitioned into segments at different sites

Discuss Question

Answer: Option C. -> All of these

Question 15. Which of the following is a disadvantage of replication?

Reduced network traffic
If the database fails at one site, a copy can be located at another site.
Each site must have the same storage capacity.
Each transaction may proceed without coordination across the network.

Discuss Question

Answer: Option C. -> Each site must have the same storage capacity.

Question 16. With failure transparency, all of the actions of a transaction are committed or none of them are committed.

True
False

Discuss Question

Answer: Option A. -> True

Question 17. Replication may use either synchronous or asynchronous distributed database technologies, although asynchronous technologies are more typical in a replicated environment.

True
False

Discuss Question

Answer: Option A. -> True

Question 18. Each site (or node) in a distributed system is subject to the same types of failure as in a centralized system.

True
False

Discuss Question

Answer: Option A. -> True

Question 19. Synchronization for pull replication is less disruptive and occurs only when needed by each site, not when a central master site thinks it is best to update.

True
False

Discuss Question

Answer: Option A. -> True

Question 20. With asynchronous technology, if any copy of a data item is updated anywhere on the network, the same update is immediately applied to all other copies or it is aborted.