Chapter 12

A _____ distributed database system will support different database management systems (DBMS) that may even support different models running under different computer systems. a. fully heterogeneous b. fully homogeneous c. homogeneous d. heterogeneous

a

A _____ request lets a single SQL statement reference data located at several different local or remote DP sites. a. distributed b. transaction c. fragmented d. remote

a

A centralized database management is subject to a problem such as _____. a. growing numbers of remote locations b. maintaining and operating small database systems c. dependence on multiple sites d. organizational flexibility of the database

a

A database management system (DBMS) must have validation, transformation, and mapping functions, as well as other functions, in order to be classified as distributed. a. True b. False

a

A distributed database management system (DDBMS) governs the storage and processing of logically related data over interconnected computer systems. a. True b. False

a

A fully distributed database management system (DBMS) must perform all the functions of a centralized DBMS, and it must handle all necessary functions imposed by the distribution of data and processing. a. True b. False

a

Current distributed database management system (DDBMS) are subject to some problems, such as the complexity of management and control. a. True b. False

a

Distributed data access was needed to support geographically dispersed business units. a. True b. False

a

Distributed processing shares a database's logical processing among two or more physically independent sites that are connected through a network. a. True b. False

a

Distribution transparency is supported by a distributed data dictionary. a. True b. False

a

In order to manage distributed data, copies or parts of the database processing functions must be distributed to all data storage sites. a. True b. False

a

Performance transparency ensures that the system finds the most cost-effective path to access remote data. a. True b. False

a

The transaction processor (TP) is the software component found in each computer that requests data. a. True b. False

a

The web is the repository for distributed data. a. True b. False

a

Which property of the CAP theorem assumes that all transaction operations take place at the same time in all nodes, as if they were executing in a single-node database? a. Consistency b. Partition tolerance c. Availability d. Performance transparency

a

_____ distributed database management systems (DDBMS) integrate multiple instances of the same DBMS over a network. a. Homogeneous b. Heterogeneous c. Fully heterogeneous d. Combination

a

_____ lets a single SQL statement access the data that are to be processed by a single remote database processor. a. remote request b. remote transaction c. distributed request d. distributed transaction

a

_____ transparency allows a physically dispersed database to be managed as though it were centralized. a. Distribution b. Transaction c. Failure d. Performance

a

_____ transparency allows data to be updated simultaneously at several network sites. a. Transaction b. Distribution c. Failure d. Performance

a

A distributed _____ contains the description of the entire database as seen by the database administrator. a. global index b. data dictionary c. global catalog d. data thesaurus

b

A distributed database is composed of several parts known as database _____. a. sections b. fragments c. partitions d. parts

b

A distributed database management system (DDBMS) must be communications-media-dependent. a. True b. False

b

A transaction processor (TP) is the software component residing on each computer that stores and retrieves data located at the site. a. True b. False

b

A(n) _____ database stores each database fragment at a single site. a. partially replicated b. unreplicated c. fully replicated d. partitioned

b

Distributed database systems do not require complex mechanisms to manage transactions and ensure the database's consistency and integrity. a. True b. False

b

Distributed processing does not require a distributed database, and a distributed database does not require distributed processing. a. True b. False

b

Distributed processing does not require: a. processing function distribution to all storage sites. b. an existing distributed database. c. interconnected networks of components. d. multiple sites to share processing chores.

b

In the single-site processing, single-site data (SPSD) scenario, all processing must be done on the end user's side of the system. a. True b. False

b

One of the advantages of a distributed database management system (DDBMS) is security. a. True b. False

b

One of the advantages of a distributed database management system (DDBMS) is that the data is located near the site with the least demand. a. True b. False

b

Rapid ad hoc data became unnecessary in the quick-response decision-making environment. a. True b. False

b

The _____ guarantees that if a portion of a transaction operation cannot be committed, all changes made at the other sites participating in the transaction will be undone to maintain a consistent database state. a. DO-UNDO-REDO protocol b. two-phase commit protocol (2PC) c. coordinator protocol d. write-ahead protocol

b

The _____ processor is the software component found in each computer that requests data. It receives and processes the application's data requests. a. database b. transaction c. data d. network

b

The _____ rule requires that all copies of data fragments be identical. a. shared fragment b. mutual consistency c. horizontal fragmentation d. replication

b

The level of transparency supported by the distributed database management system remains the same for all systems. a. True b. False

b

Under the _____ scenario, all record- and file-locking activities are performed at the end-user location. a. single-site processing, single-site data b. multiple-site processing, single-site data c. single-site processing, multiple-site data d. multiple-site processing, multiple-site data

b

_____ fragmentation refers to the division of a relation into subsets of tuples. a. Vertical b. Horizontal c. Data d. Mixed

b

_____ transparency exists when the end user or programmer must specify the database fragment names but does not need to specify where these fragments are located. a. Transaction b. Location c. Local mapping d. Fragmentation

b

_____ transparency is the highest level of transparency. The end user or programmer does not need to know that a database is partitioned. a. Performance b. Fragmentation c. Location d. Local mapping

b

A database management system needs _____ to prepare the data for presentation to the end user or to an application program. a. security b. concurrency control c. formatting d. I/O interface

c

_____ fragmentation allows a user to break a single object into two or more segments, or fragments. a. Horizontal b. Vertical c. Data d. Request

c

_____ fragmentation refers to the division of a relation into attribute subsets. a. Data b. Horizontal c. Vertical d. Mixed

c

_____ is the delay imposed by the amount of time required for a data packet to make a round trip from point A to point B a. Data distribution b. Replica transparency c. Network latency d. Network partitioning

c

_____ transparency allows the system to operate as if it were a centralized database management system. a. Heterogeneity b. Distribution c. Performance d. Failure

c

A DDBMS is subject to which restriction? a. Multiple instances of the same database should be integrated over a network. b. All database processing must be done at a single site. c. Rapid ad hoc data access is not possible. d. Remote data access is provided on a read-only basis.

d

A disadvantage of a distributed database management system (DDBMS) is: a. slower data access. b. site additions affects other operations. c. processor dependence. d. lack of standards.

d

A distributed _____ can reference several different local or remote data processing sites. a. request b. site c. data location d. transaction

d

During _____ data allocation, the database is divided into two or more disjointed parts (fragments) and stored at two or more sites. a. mixed b. replicated c. centralized d. partitioned

d

In theory, a(n) _____ can be an independent centralized database management system with proper interfaces to support remote access from other independent database management systems in the network. a. transaction processor b. application processor c. transaction manager d. data processor

d

The objective of _____ optimization is to minimize the total cost associated with the execution of a request. a. data b. remote c. transaction d. query

d