Exam 13: Distributed Databases

A form of distributed database in which all data across a network are kept continuously updated, so a user can access any data anywhere on the network and get the same answer is called a(n) ________ distributed database.

Two-phase commit is an algorithm for coordinating deletions in a distributed database management system.

With a pull strategy of replication, the ________ node determines when a database is updated.

Combining data across vertical partitions is generally more difficult than combining across horizontal partitions.

Which of the following are business conditions that encourage the use of distributed databases?

An environment in which data are distributed across all nodes, and there is a global schema, is called a(n) heterogenous environment.

The sequence of instructions required to process a transaction is called the:

All of the following are advantages of vertical partitioning EXCEPT:

The step in which a distributed database decides the order in which to execute the distributed query is called:

________ is a design goal for a distributed database, which says a user does not need to know the location of data to use the data.

Data localization involves transforming a query into fragments that explicitly reference data at one site.

Which of the following environments uses the same DBMS at each node with a central or master DBMS coordinating database access across nodes?

Failure transparency is a design goal for distributed databases that guarantees that all the actions associated with a transaction are either committed or none of them are committed.

Which of the following supports a simple path to other databases, without the benefits of one logical database?

Snapshot replication is most appropriate for:

What is data replication?

Concurrency transparency allows each transaction to appear as if it were the only activity in a distributed database management system.

In a semijoin, all of the selected attributes from every selected row are transmitted to each site.

Simple paths to other databases without the benefits of one logical database are called:

A ________ allows a single SQL statement to refer to tables in more than one remote DBMS.