Chapter 9

Transmission Control Protocol/____________________ Protocol is the standard protocol for all communication on the Internet.

Internet

Which rule for distributed databases states that the performance of functions such as adding sites, changing versions of DBMSs, creating backups, and modifying hardware should not require planned shutdowns of the entire distributed database? a. Continuous operation b. Local autonomy c. Location transparency d. Fragmentation transparency

a. Continuous operation

When users interact with an RDBMS, they use transactions. What are these types of systems called? a. OLTP b. ODBMS c. OLAP d. ODBC

a. OLTP

Which of the following contains a multipart primary key, each part of which is a foreign key to the surrounding dimension tables? a. fact table b. primary table c. dimension table d. star table

a. fact table

Which of the following is an advantage of distributed databases? a. local control of data b. easier updates of replicated data c. more complex query processing d. more complex treatment of concurrent updates

a. local control of data

The formula for message transmission time is: communication time = access delay + (data volume / X). What does X represent in the formula? a. transmission rate b. length of transmission c. lag time d. seek time

a. transmission rate

On a class diagram, the lines joining the classes represent the relationships and are called ____________________.

associations

What is the data communication method used by Web clients and Web servers to exchange data on the Internet? a. UML b. HTTP c. URL d. IIS

b. HTTP

Which rule for distributed databases states that no site should depend on another site to perform its database functions? a. Distributed transaction management b. Local autonomy c. Operating system independence d. Network independence

b. Local autonomy

If the client, in a client/server system, performs the business functions (calculations, etc.), what is this type of client known as? a. external client b. fat client c. virtual client d. thin client

b. fat client

Which type of DDBMS has at least two sites at which the local DBMS are different? a. homogeneous DDBMS b. heterogeneous DDBMS c. holistic DDBMS d. DDBMS

b. heterogeneous DDBMS

Which of the following is true about distributed databases? a. it is preferable to send a large number of short messages rather than a small number of lengthy messages b. it is preferable to send a small number of lengthy messages rather than a large number of short messages c. it is preferable to send a large number of lengthy messages rather than a small number of short messages d. it is preferable to send a large number of short messages rather than a small number of short messages

b. it is preferable to send a small number of lengthy messages rather than a large number of short messages

In which type of system are the data and actions encapsulated? a. relational b. object-oriented c. network d. parallel

b. object-oriented

With respect to the definition of data warehouse, which of the following means that data in a data warehouse represents periodic snapshots of the data, such as at the end of each month? a. nonvolatile b. time-variant c. subject-oriented d. integrated

b. time-variant

Where does a user send a message to execute steps in a method? a. to the method b. to the object c. to a class d. to a subclass

b. to the object

Which arrangement of client/server architecture uses thin clients to perform only presentation functions while a single server performs database and business functions? a. single-tier architecture b. two-tier architecture c. three-tier architecture d. multi-tier architecture

b. two-tier architecture

It is possible for local DBMSs to commit updates at some sites and undo updates at other sites. How can this inconsistency be prevented? a. using a two-step rollback b. using a two-phase commit c. using a two-phase rollback d. using a two-phase transaction

b. using a two-phase commit

Which rule for distributed databases states that users should feel as if the entire database is stored locally? a. Fragmentation transparency b. Replication transparency c. Location transparency d. Distributed query processing

c. Location transparency

What characteristic of a computer system allows it to continue to function well as utilization of the system increases? a. Reliability b. Adaptability c. Scalability d. Polymorphism

c. Scalability

Which of the following is a metalanguage and is designed for the exchange of data on the web? a. UML b. URL c. XML d. HTTP

c. XML

In a two-phase commit, what is the site that initiates the update known as? a. director b. initiator c. coordinator d. leader

c. coordinator

Which of the following contains a single-part primary key that serves as an index for the fact table and also contains other fields associated with the primary key value? a. primary table b. fact table c. dimension table d. star table

c. dimension table

With respect to the definition of data warehouse, which of the following means that the data is read-only? a. time-variant b. integrated c. nonvolatile d. subject-oriented

c. nonvolatile

When users are unaware of the steps taken by the DDBMS to update the various copies of data, what is this characteristic of the DDBMS called? a. location transparency b. fragmentation transparency c. replication transparency d. location site license

c. replication transparency

What is the overall structure of the fact table and dimension tables called? a. class schema b. data model c. star schema d. object model

c. star schema

In a centralized database design, what should you try to minimize to increase data access speed? a. the speed of the disk drive b. the number of network messages c. the number of disk accesses d. the amount of memory used

c. the number of disk accesses

What is the main purpose of data fragmentation? a. to make it easier for users to access remote data b. to place data at the location where the data is least often accessed c. to place data at the location where the data is most often accessed d. to make data access faster, whether it is local or remote

c. to place data at the location where the data is most often accessed

When users access a data warehouse, their queries usually involve aggregate data. What type of software is used to perform these queries? a. XSLT b. XSL c. OOXML d. OLAP

d. OLAP

In a three-tier system, what type of computer performs the business functions and serves as an interface for clients? a. database server b. fat client c. network server d. application server

d. application server

Which of the following refers to the association of an operation to actual program code? a. attaching b. matching c. linking d. binding

d. binding

What is the process of uncovering new knowledge, patterns, trends, and rules from the data stored in a data warehouse known as? a. fragmentation transparency b. replication transparency c. polymorphism d. data mining

d. data mining

What is it called when the data is organized by entity rather than by the application that uses the data? a. table-oriented b. row-oriented c. column-oriented d. subject-oriented

d. subject-oriented

Methods are defined during the ___________________ process.

data definition

A DDBMS is a DBMS capable of supporting and manipulating ____________________ databases.

distributed

A(n) ____________________ is the set of values that are permitted for an attribute.

domain

____________________ means that you define an object to contain both the data and its associated actions.

encapsulation

In the object-oriented representation of a database, each _______________ is represented as an object rather than a relation.

entity

A characteristic of a DDBMS that states that users do not need to be aware of the location of the data in a database is known as replication transparency.

false

A homogeneous database is one where there are at least two sites at which the local DBMSs are different.

false

A local deadlock involves one transaction that requires a record held by a second transaction at one site, while the second transaction requires a record held by the first transaction at a different site.

false

A subclass inherits the structure of a class but not its methods.

false

Accessing data using messages over a network is substantially faster than accessing data on a disk.

false

An advantage of a distributed database is that the database can handle more complex query processing.

false

If data is loaded into a data warehouse periodically, but users cannot update a data warehouse directly, the data is said to be volatile.

false

The main purpose of data fragmentation is to place data at the location where the data is least often accessed.

false

The server in a client/server system is also known as a front-end processor.

false

The term domain refers to the general structure of an object.

false

When you use thin clients in a two-tier architecture, you have a potential client maintenance problem.

false

The relationship between a superclass and a subclass is called a ____________________.

generalization

A(n) ____________________ DDBMS is a database that has the same local DBMS at each site.

homogenous

An OODBMS must provide a way to ____________________ objects; that is, the OODBMS must provide a way to distinguish between one object and another.

identify

The subclass ____________________ the structure of the class as well as its methods.

inherits

To execute the steps in a(n) ____________________, the user sends a message to the object.

method

____________________ indicates the number of objects that can be related to an individual object at the other end of the relationship.

multiplicity

Late binding lets you use the same name for different operations, which is called ____________________ in object-oriented systems.

polymorphism

With ____________________ visibility, only the class itself can view or update the value.

private

With ____________________ visibility, any other class can view or update the value of an attribute.

public

The steps taken by the DDBMS to update the various copies of data should be done behind the scenes; this is called _____________________ transparency.

replication

Web pages that display the same content for all Web clients are called ____________________ Web pages.

static

When one class is a subclass of a second class, you call the second class a ____________________ of the first class.

superclass

A DDBMS effectively contains a local DBMS at each site.

true

A distributed database is a single logical database that is physically divided among computers at several sites on a network.

true

Access delay refers to the fixed amount of time that is required for every message.

true

Access to a data warehouse is accomplished through the use of OLAP software.

true

Systems that are record-at-a-time-oriented can create performance problems in distributed systems.

true

The actions defined for a class are known as methods.

true

The beginning of a URL specifies the data communication method used by clients and servers to exchange data on the Internet.

true

The use of a three-tier architecture can help solve the scalability problem of the two-tier architecture.

true

When relational databases store complex objects, these special data types are known as BLOBs.

true

On a class diagram, a(n) ____________________ symbol precedes each attribute.

visibility