DISTRIBUTED DATABASES QUIZ

True

False

False

True

A loose collection of file that is spread to multiple locations and is interconnected by a network

A single logical database that is spread to multiple locations and is interconnected by a network

A loose collection of file that is limited to one location.

A single logical database that is limited to one location.

False

True

The same DBMS is at each node and each DBMS works independently.

A different DBMS is at each node and each DBMS works independently.

A different DBMS is at each node and a central DBMS coordinates database access.

The same DBMS is at each node and a central DBMS coordinates database access.

All of these

Maintains before and after database images

Maintains a log of transactions

Maintains appropriate concurrency control

When using many nodes with different operating systems and DBMSs and database designs.

The application's data can be somewhat out-of-date.

When transmission speeds and capacity in a network prohibit frequent refreshing of large tables.

All of these

All of the 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.

Only the joining 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 all of the rows are returned.

Each transaction may proceed without coordination across the network.

Reduced network traffic

Each site must have the same storage capacity.

If the database fails at one site, a copy can be located at another site.

Unit of work

Distributed request

Remote unit of work

Distributed unit of Work