ch2

True/False
Indicate whether the statement is true or false.

____	1.	A matrix consisting of a series of a row and column intersection is a table.

____	2.	Relations are related to each other by sharing a common entity characteristic.

____	3.	A relational DBMS is a single data repository in which data independence is maintained.

____	4.	An entity is a person, place, or thing about which data are to be collected and stored.

____	5.	A model is an exact representation of a real-world event.

____	6.	A data model represents data structures and their characteristics.

____	7.	Data modeling is usually skipped due to time constraints.

____	8.	A data model is built out of tables, rows, and columns.

____	9.	There are five types of relationships that exist between entities.

____	10.	Business rules are policies written in the employee handbook.

____	11.	Business rules help you determine the relationships that exist between entities.

____	12.	The top layer of the hierarchical model is known as the treetop.

____	13.	A segment is the equivalent of a file system's record type.

____	14.	The limitations of the hierarchical model are that none of the concepts defined by that model are in use today.

____	15.	Each segment in a hierarchical structure is referenced by a path.

____	16.	Many-to-many relationships are easily represented using a hierarchical model.

____	17.	One of the advantages of the hierarchical model is the ease of maintaining data integrity.

____	18.	Hierarchal databases became popular in the 1980s.

____	19.	The only relationship type supported by the hierarchical model is 1:1.

____	20.	The hierarchical model was the first to define a standard DML and DDL.

____	21.	The DBTG report contained specifications for a schema and subschema.

____	22.	In 1975, it was decided that all databases should conform to the SPARC standard.

____	23.	In network database terminology, 1:M relationships are represented using a database table.

____	24.	In the network model, an entity can have more than one owner.

____	25.	In the network model, it is possible for a member to exist without an owner.

____	26.	One of the disadvantages of the network model was the lack of structural independence.

____	27.	The developer of the relational model worked for Microsoft.

____	28.	SQL makes pure ad hoc queries a reality.

____	29.	Only 1:M and M:N relationships can be represented in a relational schema.

____	30.	Ad hoc query capability was introduced in the relational model.

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____	31.	A relational database is a group of ____.
a.	common fields	
b.	field values	
c.	records	
d.	tables	

____	32.	A table is a matrix consisting of a series of row and column ____.
a.	links	
b.	intersections	
c.	systems	
d.	models	

____	33.	One of the advantages of a relational database model is ____.
a.	structural dependence	
b.	conceptual complexity	
c.	easier database design	
d.	complex database design	

____	34.	The most important advantages of the hierarchical database model are ____.
a.	conceptual simplicity, security, integrity, diversity, and security	
b.	security, efficiency, diversity, simplicity, and integrity	
c.	integrity, efficiency, diversity, independence, and simplicity	
d.	conceptual simplicity, security, independence, integrity, and efficiency	

____	35.	Using network terminology, a relationship is called a(n) ____.
a.	member	
b.	owner	
c.	set	
d.	table	

____	36.	The hierarchical database model is based on a ____.
a.	tree structure	
b.	lack of a parent segment	
c.	lack of a child segment	
d.	matrix	

____	37.	The hierarchical database model uses the hierarchic sequence that always starts at the ____ of the tree.
a.	right side	
b.	left side	
c.	top 	
d.	bottom	

____	38.	The hierarchical database model depicts a set of ____ relationships.
a.	M:1	
b.	1:1	
c.	1:M	
d.	M:N	

____	39.	Given its parent/child structure, the hierarchical model yields integrity and consistency; there cannot be ____.
a.	a root	
b.	a large amount of data	
c.	a child without a parent	
d.	many transactions	

____	40.	The hierarchical database is not very efficient when handling ____.
a.	large amounts of data	
b.	few transactions	
c.	many transactions	
d.	1:M relationships	

____	41.	The hierarchical database models ____.
a.	have no implementation limitations	
b.	promote database integrity	
c.	have very strict standards	
d.	have a simple navigational system	

____	42.	A relational database model ____.
a.	does not require substantial hardware and system software overhead	
b.	does not promote "islands of information" problems	
c.	allows trained people to use a good system poorly	
d.	lets the user operate in a human logical environment	

____	43.	The OODM ____.
a.	adds semantic content	
b.	has standards	
c.	has a simple navigational system	
d.	has a low system overhead that speeds transactions	

____	44.	The network database models have a(n) ____.
a.	navigational system that yields simple design	
b.	simple system that promotes efficiency	
c.	owner/member relationship that promotes database integrity	
d.	great deal of structural independence	

____	45.	Database models were developed to ____.
a.	model real-world events or conditions	
b.	deposit data within a single file	
c.	keep data within multiple data repositories	
d.	allow DBMSs to maintain loose control over the database activities	

____	46.	Which of the following was NOT produced by the DBTG of CODASYL?
a.	Standard network specifications for a network schema	
b.	Standard network specifications for a network sub-schema	
c.	Standard specifications for a data management language	
d.	Standard diagrams for database modeling known as ERD	

____	47.	The RDBMS ____.
a.	performs functions provided by the hierarchical and network DBMS system	
b.	does not manage data structures	
c.	allows the user/designer to ignore the logical view of the database	
d.	does not manage the details of physical storage	

____	48.	Because an RDBMS hides the system's complexity from the user/designer, ____.
a.	it does not exhibit data independence	
b.	it does not exhibit structural independence	
c.	data management is easier	
d.	data management is very difficult	

____	49.	John is working in the customer table and needs to know what customers are located in Florida.  To find the information he would ____.
a.	create a new table	
b.	create a new form	
c.	create a new query	
d.	utilize the Database Wizard	

____	50.	Database models can be grouped into two categories: conceptual models and ____ models.
a.	implementation	
b.	logical	
c.	physical	
d.	query	

____	51.	In a network database each set is composed of two record types: an owner record and a ____ record.
a.	root	
b.	child	
c.	member	
d.	renter	

____	52.	Each row in the relational table is known as an entity ____.
a.	instance	
b.	relationship	
c.	attribute	
d.	model	

____	53.	Classes are organized into a class ____.
a.	method	
b.	hierarchy	
c.	system	
d.	object	

____	54.	In response to the increasing complexity of applications, two new data models emerged: the object-oriented data model and the ____ relational data model.
a.	extended	
b.	flat-file	
c.	hierarchical	
d.	entity	

____	55.	The ____ model is the relational model’s challenge to the OODM.
a.	ERD	
b.	network	
c.	hierarchical	
d.	KR	

____	56.	Which of the following data models contains the least semantics?
a.	Hierarchical	
b.	Network	
c.	Relational	
d.	Object-oriented	

____	57.	Which of the following data models contains the most semantics?
a.	Hierarchical	
b.	Network	
c.	Relational	
d.	Object-oriented	

____	58.	Which of the following data models are dependent on their physical structure?
a.	Object-oriented	
b.	Relational	
c.	Semantic	
d.	Hierarchical	

____	59.	Which of the following database models is NOT still in use today?
a.	Object-oriented	
b.	Network	
c.	Relational	
d.	ERD	

____	60.	A data model must represent the ____ world as closely as possible.
a.	machine	
b.	logical	
c.	real	
d.	abstract	

____	61.	What modern development has dramatically changed the direction database technology was moving in?
a.	Object-oriented programming	
b.	The Internet	
c.	Y2K	
d.	Mainframes	

____	62.	A way of classifying data models is by degree of ____.
a.	difficulty	
b.	knowledge	
c.	abstraction	
d.	unification	

____	63.	Which of the following is not a degree of abstraction as defined by ANSI/SPARC?
a.	Conceptual	
b.	Physical	
c.	Internal	
d.	External	

____	64.	Successful database design is first and foremost based on ____.
a.	resource use	
b.	cost savings	
c.	programming ease	
d.	end-user requirements	

____	65.	Which of the following databases does NOT provide structural independence?
a.	network	
b.	relational	
c.	entity relationship	
d.	object oriented	

____	66.	The ____ model presents a global view of the database.
a.	network	
b.	physical	
c.	conceptual	
d.	logical	

____	67.	A(n) ____ model is independent of both hardware and software.
a.	conceptual	
b.	external	
c.	developmental	
d.	logical	

____	68.	The ____ model adapts a conceptual model to a specific DBMS.
a.	entity	
b.	internal	
c.	external	
d.	database	

____	69.	Which of the following requires the most detail in the internal model?
a.	Network	
b.	Relational	
c.	Semantic	
d.	Entity relationship	

____	70.	Which model represents the end user’s view of the database?
a.	Internal	
b.	Conceptual	
c.	Physical	
d.	External	

____	71.	Which model operates at the lowest level of abstraction?
a.	Conceptual	
b.	Internal	
c.	External	
d.	Physical	

____	72.	What type of relationship is expressed with the phrase “Painter paints Painting”?
a.	1:M	
b.	1:1	
c.	M:1	
d.	M:N	

____	73.	What type of relationship is expressed with the phrase “Employee manages Store”?
a.	1:M	
b.	1:1	
c.	M:1	
d.	M:N	

____	74.	What type of relationship is expressed with the phrase “Student takes Class”?
a.	1:M	
b.	1:1	
c.	M:1	
d.	M:N	

____	75.	Which of the following is least likely to be a business rule as relates to data modeling?
a.	A customer may make many payments on an account.	
b.	A machine operator may not work more than 10 hours in a 24-hour period.	
c.	A training session cannot be scheduled for fewer than 10 employees or more than 30 employees.	
d.	Casual Fridays take place in the summer.	

Completion
Complete each statement.

	76.	Data in two or more tables can be related to each other by means of a(n) ____________________ entity characteristic.

	77.	The RDBMS performs the same basic functions provided by the hierarchical and ____________________ DBMS systems.

	78.	The ____________________ database is a collection of records that is logically organized to conform with the upside-down tree.

	79.	In the relational model, another name for a table is a(n) ____________________.

	80.	The network ____________________ is the conceptual organization of the entire database as viewed by the database administrator.

	81.	The ____________________ defines the portion of the database “seen” by the application programs that actually produce the desired information from the data contained within the database.

	82.	A(n) ____________________ is a matrix consisting of a series of row/column intersections.

	83.	A(n) ____________________ is a characteristic of an entity.

	84.	A(n) ____________________ describes an association among two (or more) entities.

	85.	The relationship described by the phrase “the Customer generates the Invoice” is ____________________.

	86.	A(n) ____________________ is a brief, concise, and unambiguous description of a policy.

	87.	The first database model developed was the ____________________ model.

	88.	In a hierarchical model, each level of the tree is called a(n) ____________________.

	89.	The top level in a hierarchical model is known as the ____________________.

	90.	A relational ____________________ is a visual representation of a relational database's entities, attributes, and relationships.

	91.	The ____________________ model was created to represent complex data relationships more effectively than the hierarchical model could and to impose a database standard.

	92.	In the network model, a(n) ____________________ language is used to define data characteristics.

	93.	In 1975, the ANSI _____________________________________________ augmented the network model database standards.

	94.	In network database terminology, a relationship is called a(n) ____________________.

	95.	In network model terminology, each set is composed of a(n) ____________________ and a member.

	96.	____________________ relationships are easier to represent in the network model than the hierarchical model.

	97.	The ____________________ model is to database design what the automatic transmission is to cars.

	98.	The query language for a relational database is _________________________.

	99.	The ____________________ data model was developed by Peter Chen.

	100.	A(n) ____________________ is a person, place, or thing about which information is stored.

Essay

	101.	List the different types of relationships and provide an example of each.

	102.	When designing a database, it is important to understand the business rules.  Where do these rules come from?  How do you go about gathering them?  What are some of the problems that might occur when gathering business rules and how can you avoid them?

	103.	List at least three of the advantages of using a hierarchical database.

ch2
Answer Section

TRUE/FALSE

	1.	ANS:	T	PTS:	1	REF:	36

	2.	ANS:	T	PTS:	1	REF:	36

	3.	ANS:	T	PTS:	1	REF:	37

	4.	ANS:	T	PTS:	1	REF:	30

	5.	ANS:	F	PTS:	1	REF:	29

	6.	ANS:	T	PTS:	1	REF:	29

	7.	ANS:	F	PTS:	1	REF:	29

	8.	ANS:	F	PTS:	1	REF:	30

	9.	ANS:	F	PTS:	1	REF:	30

	10.	ANS:	F	PTS:	1	REF:	31

	11.	ANS:	T	PTS:	1	REF:	31

	12.	ANS:	F	PTS:	1	REF:	33

	13.	ANS:	T	PTS:	1	REF:	33

	14.	ANS:	F	PTS:	1	REF:	33

	15.	ANS:	T	PTS:	1	REF:	33

	16.	ANS:	F	PTS:	1	REF:	33

	17.	ANS:	T	PTS:	1	REF:	44

	18.	ANS:	F	PTS:	1	REF:	33

	19.	ANS:	F	PTS:	1	REF:	33

	20.	ANS:	F	PTS:	1	REF:	35

	21.	ANS:	T	PTS:	1	REF:	34

	22.	ANS:	F	PTS:	1	REF:	46

	23.	ANS:	T	PTS:	1	REF:	35

	24.	ANS:	T	PTS:	1	REF:	35

	25.	ANS:	F	PTS:	1	REF:	35

	26.	ANS:	T	PTS:	1	REF:	35

	27.	ANS:	F	PTS:	1	REF:	36

	28.	ANS:	T	PTS:	1	REF:	44

	29.	ANS:	F	PTS:	1	REF:	39

	30.	ANS:	T	PTS:	1	REF:	44-45

MULTIPLE CHOICE

	31.	ANS:	D	PTS:	1	REF:	36

	32.	ANS:	B	PTS:	1	REF:	36

	33.	ANS:	C	PTS:	1	REF:	36

	34.	ANS:	D	PTS:	1	REF:	44

	35.	ANS:	C	PTS:	1	REF:	35

	36.	ANS:	A	PTS:	1	REF:	33

	37.	ANS:	B	PTS:	1	REF:	33-34

	38.	ANS:	C	PTS:	1	REF:	33

	39.	ANS:	C	PTS:	1	REF:	33

	40.	ANS:	B	PTS:	1	REF:	34

	41.	ANS:	B	PTS:	1	REF:	44

	42.	ANS:	D	PTS:	1	REF:	36

	43.	ANS:	A	PTS:	1	REF:	41

	44.	ANS:	C	PTS:	1	REF:	35

	45.	ANS:	A	PTS:	1	REF:	29

	46.	ANS:	D	PTS:	1	REF:	34-35

	47.	ANS:	A	PTS:	1	REF:	36

	48.	ANS:	C	PTS:	1	REF:	36

	49.	ANS:	C	PTS:	1	REF:	36

	50.	ANS:	A	PTS:	1	REF:	43-46

	51.	ANS:	C	PTS:	1	REF:	35

	52.	ANS:	A	PTS:	1	REF:	39

	53.	ANS:	B	PTS:	1	REF:	42

	54.	ANS:	A	PTS:	1	REF:	33

	55.	ANS:	A	PTS:	1	REF:	43

	56.	ANS:	A	PTS:	1	REF:	45

	57.	ANS:	D	PTS:	1	REF:	45

	58.	ANS:	D	PTS:	1	REF:	45

	59.	ANS:	B	PTS:	1	REF:	45

	60.	ANS:	C	PTS:	1	REF:	45

	61.	ANS:	B	PTS:	1	REF:	43

	62.	ANS:	C	PTS:	1	REF:	46

	63.	ANS:	B	PTS:	1	REF:	46

	64.	ANS:	D	PTS:	1	REF:	46

	65.	ANS:	A	PTS:	1	REF:	44

	66.	ANS:	C	PTS:	1	REF:	48

	67.	ANS:	A	PTS:	1	REF:	48

	68.	ANS:	B	PTS:	1	REF:	48

	69.	ANS:	A	PTS:	1	REF:	49

	70.	ANS:	D	PTS:	1	REF:	47

	71.	ANS:	D	PTS:	1	REF:	49

	72.	ANS:	A	PTS:	1	REF:	30

	73.	ANS:	B	PTS:	1	REF:	30

	74.	ANS:	D	PTS:	1	REF:	30

	75.	ANS:	D	PTS:	1	REF:	31

COMPLETION

	76.	ANS:	common

PTS:	1	REF:	36

	77.	ANS:	network

PTS:	1	REF:	36

	78.	ANS:	hierarchical

PTS:	1	REF:	33

	79.	ANS:	relation

PTS:	1	REF:	36

	80.	ANS:	schema

PTS:	1	REF:	34

	81.	ANS:	subschema

PTS:	1	REF:	34

	82.	ANS:	table

PTS:	1	REF:	36

	83.	ANS:	attribute

PTS:	1	REF:	30

	84.	ANS:	relationship

PTS:	1	REF:	30

	85.	ANS:	
one-to-many
one to many
1 to many
1:M

PTS:	1	REF:	30

	86.	ANS:	business rule

PTS:	1	REF:	31

	87.	ANS:	hierarchical

PTS:	1	REF:	33

	88.	ANS:	segment

PTS:	1	REF:	33

	89.	ANS:	root

PTS:	1	REF:	33

	90.	ANS:	schema

PTS:	1	REF:	36

	91.	ANS:	network

PTS:	1	REF:	34

	92.	ANS:	data management

PTS:	1	REF:	35

	93.	ANS:	
SPARC
Standards Planning and Requirements Committee

PTS:	1	REF:	46

	94.	ANS:	set

PTS:	1	REF:	35

	95.	ANS:	owner

PTS:	1	REF:	35

	96.	ANS:	
M:N
Many-to-many
many to many

PTS:	1	REF:	45

	97.	ANS:	relational

PTS:	1	REF:	36

	98.	ANS:	
SQL
structured query language

PTS:	1	REF:	37

	99.	ANS:	
ER
entity relationship

PTS:	1	REF:	38

	100.	ANS:	entity

PTS:	1	REF:	30

ESSAY

	101.	ANS:	
There are three types of relationships:
1) One-to-One (1:1) relationships: Employee manages Store
2) One-to-Many (1:M) relationships: Painter paints Painting
3) Many-to-Many (M:N or M:M) relationships: Student takes Class

PTS:	1	REF:	30

	102.	ANS:	
The main sources of business rules are company managers, policy makers, department managers, and written documentation–such as a company's procedures, standards, or operations manuals. A faster and more direct source of business rules is direct interviews with end users. Unfortunately, because perceptions differ, end users sometimes are a less-reliable source when it comes to specifying business rules. For example, a maintenance department mechanic may believe that any mechanic may initiate a maintenance procedure, when actually only mechanics with inspection authorization may perform such a task. Such a distinction may seem trivial, but it can have major legal consequences. Although end users are crucial contributors to the development of business rules, it pays to verify end-user perceptions. Often, interviews with several people who perform the same job can yield very different perceptions of what the job components are. While such a discovery may point to "management problems," that general diagnosis does not help the database designer. Given the discovery of such problems, the database designer's job is to reconcile such differences and to verify the results of the reconciliation to ensure that the business rules are appropriate and accurate.

PTS:	1	REF:	31

	103.	ANS:	
Any three of the following:
1) Conceptual simplicity. The relationship between the various layers of the model is logically simple. Therefore, it becomes easier to view the database conceptually, thus making its design process simpler.
2) Database security. Database security is provided and enforced by the DBMS. Therefore, security is enforced uniformly throughout the system, without having to rely on the efforts of individual applications programmers who may have very different ideas about the extent and type of required security.
3) Data independence. The DBMS creates an environment in which data independence can be maintained, thereby substantially decreasing programming effort and program maintenance. (Data independence exists when a change in a data type will be automatically cascaded throughout the database by the DBMS, thus eliminating the need to make changes in the program segments that reference the changed data type.)
4) Database integrity. Given the parent/child relationship, there is always a link between the parent segment and its child segment(s). Because the child segment is always automatically referenced to its parent, the hierarchical model promotes database integrity.
5) Efficiency. The hierarchical data model is very efficient when a database contains a large volume of data in 1:M relationships and when users require large numbers of transactions, using data having relationships that are fixed over time.

PTS:	1	REF:	33 | 44