DRM Ch. 12 Quiz

A distributed database must: Question options: present a single logical database that is physically distributed. provide consistency among data copies. keep track of data locations. all of the above.

All of the Above

Which of the following are factors in deciding on database distribution strategies? Question options: Reliability needs Organizational forces Frequency of data access All of the above

All of the Above

Which of the following is an advantage to data replication? Question options: Fast response Reliability Node decoupling All of the above

All of the Above

Which of the following is true of data replication? Question options: Faster response Additional storage requirements Node decoupling All of the above

All of the Above

________ ensures that a transaction is successfully completed or else it is aborted. Question options: TCP/IP protocol Failure protocol Commit protocol None of the above

Commit Protocol

Which of the following is true about horizontal partitioning? Question options: Data are less secure. There is consistent access speed. Data can be stored to optimize local access. None of the above.

Data can be stored to optimize local access

A(n) ________ is a database stored on multiple computers in multiple locations that are NOT connected by a data communications link. Question options: unlinked database decentralized database distributed database data repository

Decentralized database

Which of the following environments uses a different DBMS at each node and supports local databases for unique data requests? Question options: Homogeneous; cross-linked Gateways; local Centralized; minimum Heterogeneous; federated

Heterogeneous; federated

In a distributed database, a transaction that requires reference to data at one or more nonlocal sites is called a ________ transaction. Question options: tight global link loose

Global

Which of the following environments uses the same DBMS at each node with a central or master DBMS coordinating database access across nodes? Question options: Federated; nonautonomous Homogeneous; nonautonomous Centralized; minimum Centralized; maximum

Homogeneous; nonautonomous

Which of the following characterizes homogeneous environments? Question options: Some users require only local access Cross-linked systems easily communicate Same DBMS used at all locations Contains simple pathways

Same DBMS used at all locations

With a pull strategy of replication, the ________ node determines when a database is updated. Question options: source target user all of the above

Target

One way to generate store and forward messages for completed transactions to be broadcast across a network is through the use of: Question options: functions. SQL statements. stored procedures. triggers.

Triggers

The sequence of instructions required to process a transaction is called the: Question options: unit of work. rollback. commit. logical program unit.

Unit of Work

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: Question options: location transparency. linear run. transaction CPU transparency. concurrency transparency.

concurrency transparency

A ________ allows a single SQL statement to refer to tables in more than one remote DBMS. Question options: join SQL statement distributed request data transfer command distributed UOW

distributed request

All of the following are advantages of vertical partitioning EXCEPT: Question options: security. easier to set up than horizontal partitioning. ease of querying. efficiency.

easier to set up than horizontal

With ________, users can act as if all the data were located at a single node. Question options: client-based control local autonomy location transparency all of the above

location transparency

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: Question options: data accessibility. replication accessibility. replication transparency. location transparency.

replication transparency

A joining operation in which only the joining attribute from one site is transmitted to the other site is called a(n): Question options: key data element transfer. attribute linkup. key data element join. semijoin.

semijoin