PRELIM CHAPTER 2 Flashcards
(T or F) Designers, programmers, and end users see data in different ways
T
(T or F) Different views of same data lead to designs that reflect the organization’s operation
F
Different views of same data lead to designs that do not reflect organization’s operation
reduces complexities of database design
- data processing
- data modeling
- data management
- data abstraction
data modeling
Various degrees of ____________ help reconcile varying views of same data
- data processing
- data modeling
- data management
- data abstraction
data abstraction
Relatively simple representations of complex real-world data structures
- data models
- data systems
- database
- data
data models
an abstraction of a real-world object or event
- files
- data
- model
- information
model
(T or F) Data modeling is iterative and progressive
T
(T or F) End users have different views and needs for data
T
organizes data for various users and it is an abstraction
- database
- DBMS
- file systems
- data model
data model
anything about which data are to be collected and stored
- Entity
- Attribute
- Relationship
- Constraint
Entity
a characteristic of an entity
- Entity
- Attribute
- Relationship
- Constraint
Attribute
describes an association among entities
- Entity
- Attribute
- Relationship
- Constraint
Relationship
a restriction placed on the data
- Entity
- Attribute
- Relationship
- Constraint
Constraint
3 types of relationships among entities:
- One-to-many (1:M) relationship
- Many-to-many (M:N or M:M) relationship
- One-to-one (1:1) relationship
__________ are descriptions of policies, procedures, or principles within a specific organization
Business Rules
____________ describe characteristics of data as viewed by the
company
Business Rules
*Sources of business rules:
*Company __________
*__________ makers
*__________ managers
*__________ documentation
*Direct __________ with end users
managers
Policy
Department
Written
interviews
__________ translate into entities
- nouns
- verbs
- relationships
- naming
- names
Nouns
__________ translate into relationships among entities
- nouns
- verbs
- relationships
- naming
- names
verbs
__________ are bidirectional
- nouns
- verbs
- relationships
- naming
- names
relationships
- Proper naming:
- Facilitates __________ between parties
- Promotes __________
communication
self-documentation
__________ occurs during translation of business rules to data model components
- nouns
- verbs
- relationships
- naming
- names
naming
__________ should make the object unique and distinguishable from other objects
- nouns
- verbs
- relationships
- naming
- names
Names
___________ should also be descriptive of objects in the environment and be familiar to users
- nouns
- verbs
- relationships
- naming
- names
Names
(T or F) Relational models were considered impractical in 1970
T
Matrix consisting of row/column intersections
- names
- table
- model
- tuple
table
the ___________ model is developed by E.F. Codd (IBM) in 1970
relational
Each row in a relation is called a ___________
- names
- table
- model
- tuple
tuple
___________ was conceptually simple at expense of computer overhead
- names
- table
- model
- tuple
model
RDBMS means ?
Relational data management system
Performs same functions provided by hierarchical model
- RDBMS
- DBMS
- relational diagram
- relational table
Relational data management system (RDBMS)
Hides complexity from the user
- RDBMS
- DBMS
- relational diagram
- relational table
Relational data management system (RDBMS)
Representation of entities, attributes, and relationships
- RDBMS
- DBMS
- relational diagram
- relational table
Relational diagram
Representation of entities, attributes, and relationships
- RDBMS
- DBMS
- relational diagram
- relational table
relational table
