Exam 13: Distributed Databases

A(n) ________ is a database stored on multiple computers in multiple locations that are NOT connected by a data communications link.

Which of the following is true of distributed databases?

With an asynchronous distributed database, all data across the network is continuously kept up to date.

The purpose of time-stamping is to allow transactions to be processed in parallel.

Replication transparency allows a programmer or user to treat a replicated data item as if it were a single item at a single node.

What business conditions encourage the use of distributed databases?

Describe the range of distributed database environments.

Which of the following is true of data replication?

A distributed database is NOT just a collection of files.

Users of distributed database systems always need to know the location of the data.

When separate copies of data are stored at each of two or more sites, it is called replication.

The transaction processor at each site maintains an appropriate concurrency scheme to ensure data integrity during parallel execution of transactions at that site.

A transaction that requires reference to data at one or more nonlocal sites to satisfy the request is a global transaction.

What are the three different kinds of transparencies used in distributed database management systems?

What is the difference between a local transaction and a global transaction?

In a push replication strategy, the target, not the source, controls when a local database is updated.

Explain the difference between a synchronous and asynchronous distributed database.

All of the following are disadvantages of data replication EXCEPT:

________ is an application that can effectively employ snapshot replication in a distributed environment.

A distributed database may require more costly and complex software than a centralized database.