Relationship Types, Sets, Roles and Structural Constraints

Question 1

cardinality ratio

Answer 1

maximum number of relationship instances an entity can participate in

Question 2

participation constraint (or minimum cardinality constraint)

Answer 2

minimum number of relationship instances an entity can participate in

Question 3

total participation

Answer 3

every entity must be related to another entity

Question 4

partial participation

Answer 4

part of the set of entities are related to another entity

Question 5

weak entity types

Answer 5

entities that do not have a key attribute

Question 6

identifying or owner entity type

Answer 6

entity type used with an attribute to define a relationship to another entity

Question 7

identifying relationship

Answer 7

relationship that links weak entity type to its owner

Question 8

partial key

Answer 8

attribute that can uniquely identify weak entities that are related to the same owner entity

Question 9

aggregation in UML

Answer 9

representation of a relationship between an entity and its components