WGU C175 Study Notecards
Flat Files - ANS-a file having no internal hierarchy
Hashed Files - ANS-A file that has been encrypted for security purposes.
Heap File - ANS-An unsorted set of records.
Information - ANS-The transformation of raw data into useful facts.
Punch Card - ANS-A card that is perforated and can hold commands or data.
Structured Data - ANS-Information with a high degree of organization.
Unstructured Data - ANS-Information that does not have structure (such as text)
Binary Relationship - ANS-A relationship between two entity types.
Unary Relationship - ANS-An associate occurrence of an entity type with other
occurrences of the same entity type.
Cardinality - ANS-The maximum number of entities that can be involved in a particular
relationship.
E-R Model
*E-R = Entity - Relationship - ANS-Diagram of entities together with their attributes and
the relationship among them.
Intersection Data - ANS-It is data that describes a many-to-many relationship.
Modality - ANS-It is a minimum number of entity occurrences that can be involved in a
relationship.
One-to-one Binary Relationship - ANS-It means that a single occurrence of one entity
type can be associated with a single occurrence of the other entity type and vice versa.
Ternary Relationship - ANS-Involves three different entity types.
, Unique identifier - ANS-It is used to uniquely identify each record in a database table.
Attribute - ANS-A property, characteristic, or fact that we know about an entity.
"A salesperson works in one office."
What is the name of this relationship? - ANS-One-to-one binary relationship
"A salesperson sells to many customers."
What is the name of this relationship? - ANS-One-to-many binary relationship
"A salesperson is authorized to sell many products, and a product can be sold by many
salespersons."
What is the name of this relationship? - ANS-Many-to-many binary relationship
What is the positioning and meaning for Cardinality and Modality on an E-R model? -
ANS-Cardinality is the outer symbol; represents the maximum.
Modality is the inner symbol; represents the minimum.
"A salesperson works in a minimum of one and a maximum of one office, and an office
may be occupied by or assigned to a minimum of zero and a maximum of one
salesperson." - ANS-
"A salesperson may have no customers or many customers." - ANS-
Describe the ER model for "Each salesperson is authorized to sell to at least one or
many products, and each product can be sold by at least one or many salespeople." -
ANS-
"One salesperson backs-up another salesperson."
What is the name of this model? - ANS-One-to-one unary relationship
"A salesperson manages zero to many other salespersons, and a salesperson is
managed by exactly one other salesperson."
Flat Files - ANS-a file having no internal hierarchy
Hashed Files - ANS-A file that has been encrypted for security purposes.
Heap File - ANS-An unsorted set of records.
Information - ANS-The transformation of raw data into useful facts.
Punch Card - ANS-A card that is perforated and can hold commands or data.
Structured Data - ANS-Information with a high degree of organization.
Unstructured Data - ANS-Information that does not have structure (such as text)
Binary Relationship - ANS-A relationship between two entity types.
Unary Relationship - ANS-An associate occurrence of an entity type with other
occurrences of the same entity type.
Cardinality - ANS-The maximum number of entities that can be involved in a particular
relationship.
E-R Model
*E-R = Entity - Relationship - ANS-Diagram of entities together with their attributes and
the relationship among them.
Intersection Data - ANS-It is data that describes a many-to-many relationship.
Modality - ANS-It is a minimum number of entity occurrences that can be involved in a
relationship.
One-to-one Binary Relationship - ANS-It means that a single occurrence of one entity
type can be associated with a single occurrence of the other entity type and vice versa.
Ternary Relationship - ANS-Involves three different entity types.
, Unique identifier - ANS-It is used to uniquely identify each record in a database table.
Attribute - ANS-A property, characteristic, or fact that we know about an entity.
"A salesperson works in one office."
What is the name of this relationship? - ANS-One-to-one binary relationship
"A salesperson sells to many customers."
What is the name of this relationship? - ANS-One-to-many binary relationship
"A salesperson is authorized to sell many products, and a product can be sold by many
salespersons."
What is the name of this relationship? - ANS-Many-to-many binary relationship
What is the positioning and meaning for Cardinality and Modality on an E-R model? -
ANS-Cardinality is the outer symbol; represents the maximum.
Modality is the inner symbol; represents the minimum.
"A salesperson works in a minimum of one and a maximum of one office, and an office
may be occupied by or assigned to a minimum of zero and a maximum of one
salesperson." - ANS-
"A salesperson may have no customers or many customers." - ANS-
Describe the ER model for "Each salesperson is authorized to sell to at least one or
many products, and each product can be sold by at least one or many salespeople." -
ANS-
"One salesperson backs-up another salesperson."
What is the name of this model? - ANS-One-to-one unary relationship
"A salesperson manages zero to many other salespersons, and a salesperson is
managed by exactly one other salesperson."
