Exam 13: Distributed Databases

In a heterogeneous environment, not all users use the same DBMS.

Data replication allowing for each transition to proceed without coordination is called:

A replicated database with snapshots is very manageable.

Applications such as decision support or data warehousing often do not require current data and are supported by periodic snapshots.

Local autonomy means that data are not accessible from remote sites.

A design goal for distributed databases to allow programmers to treat a data item replicated at several sites as though it were at one site is called:

Discuss the different types of data replication.

What are the three steps that a distributed DBMS uses to develop a query plan?

What are some of the advantages and disadvantages of a distributed database?

________ is a design goal for a distributed database that says a site can independently administer and operate its database.

A distributed database must:

A design goal for distributed databases that states that although a distributed database runs many transactions, it appears that a given transaction is the only one in the system is called:

Horizontal partitioning is implemented by placing some rows of a table at one site and other rows at another site.

A centralized strategy has ________ expandability.

A distributed unit of work allows a single SQL UPDATE statement to update data at more than one location.

A transaction manager is an algorithm that coordinates updates or aborts them.

A distributed database is a single logical database spread physically across computers in multiple locations that are connected by a data communications link.

Scalability is the ability to grow, reduce in size, and become more heterogeneous as the needs of the business change.

Applications that can tolerate out-of-date data are not the best candidates for data replication.

A synchronized replication strategy has a(n) ________ reliability.