OMIS 452 Quiz 5-6 Questions and Answers
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3
Practice questions for this set
Learn 1 /7 Study with Learn
an entity instance of one type is related to at most one entity instance of the other
type
Choose an answer
1 data model 2 binary relationship
3 entity class 4 one-to-one relationship
Don't know?
, Terms in this set (58)
data model is a plan, or a blueprint for a database design
a set of constraints and conventions used to create data models.
the things in the users; world are represented by entities and the
entity-relationship model
associations among those things are represented by
relationships.
extended E-R model subtypes added to the model, most commonly used today
Entity is something that users want to track
entity class entities of a given type
entity instance is the occurrence of a particular entity such as, CUSTOMER 12345
attributes describe the characteristics of the entities
identifiers attributes that name, or identify, entity instances
composite identifiers identifiers that consist of one or more attributes
relationship classes associations among entity classes
relationship instances associations among entity instances
degree of the relationship the number of entity classes in the relationship
binary relationship relationships with the degree of 2
ternary relationship relationships with the degree of 3
cardinality in the E-R model relationships are classified by their count
Save
3
Practice questions for this set
Learn 1 /7 Study with Learn
an entity instance of one type is related to at most one entity instance of the other
type
Choose an answer
1 data model 2 binary relationship
3 entity class 4 one-to-one relationship
Don't know?
, Terms in this set (58)
data model is a plan, or a blueprint for a database design
a set of constraints and conventions used to create data models.
the things in the users; world are represented by entities and the
entity-relationship model
associations among those things are represented by
relationships.
extended E-R model subtypes added to the model, most commonly used today
Entity is something that users want to track
entity class entities of a given type
entity instance is the occurrence of a particular entity such as, CUSTOMER 12345
attributes describe the characteristics of the entities
identifiers attributes that name, or identify, entity instances
composite identifiers identifiers that consist of one or more attributes
relationship classes associations among entity classes
relationship instances associations among entity instances
degree of the relationship the number of entity classes in the relationship
binary relationship relationships with the degree of 2
ternary relationship relationships with the degree of 3
cardinality in the E-R model relationships are classified by their count
