Download Entity-Relationship Model and Data Management Terms and more Quizzes Information Technology in PDF only on Docsity! TERM 1 Entity-relationship model DEFINITION 1 a logical representation of the data for an organization or for a business area, using entities for categories of data and relationships for associations between entities TERM 2 business rule DEFINITION 2 statement that defines or constrains some aspect of the businessintended to assert business structure or control/influence the behavior of the business TERM 3 data name requirements DEFINITION 3 relate to business, not technical characteristics be meaningful be unique be readable be composed of words taken from an approved list be repeatable follow a standard syntax TERM 4 term DEFINITION 4 word or phrase that has a specific meaning for the business TERM 5 fact DEFINITION 5 association between to or more terms TERM 6 entity DEFINITION 6 person, place, object, event, or concept in the user envt about which the org wishes to maintain data TERM 7 entity type DEFINITION 7 collection of entities that share common properties/characteristics TERM 8 entity instance DEFINITION 8 single occurrence of an entity type TERM 9 strong entity type DEFINITION 9 exists independently of other entity types TERM 10 weak entity type DEFINITION 10 exists dependently of another entity type TERM 21 derived attribute DEFINITION 21 attribute whose values can be calculated from related attribute valuesex: entity = years employed, when you also have entity = date employed TERM 22 identifier DEFINITION 22 attribute (or combo of attributes) whose value distinguishes instances of an entity type TERM 23 composite identifier DEFINITION 23 identifier that consists of a composite attribute TERM 24 rules for naming attributes DEFINITION 24 unique noun or noun phrase follow a standard format similar attributes should use the same qualifiers and classes TERM 25 relationship type DEFINITION 25 meaningful association between or among entity types TERM 26 associative entity DEFINITION 26 associates the instances of one or more entity types and contains attributes that are peculiar to the relationship between those entity instances TERM 27 degree DEFINITION 27 number of entity types that participate in a relationship TERM 28 unary relationship DEFINITION 28 relationship between instances of a single entity type TERM 29 binary relationship DEFINITION 29 relationship between the instances of two entity types TERM 30 ternary relationship DEFINITION 30 simultaneous relationship among the instances of 3 entity types TERM 31 cardinality constraint DEFINITION 31 rule that specifies the number of instances of one entity that can or must be associated with each instances of another entity TERM 32 minimum cardinality DEFINITION 32 minimum number of instances of one entity that may be associated with each instance of another entity TERM 33 maximum cardinality DEFINITION 33 max number of instances of one entity that may be associated with each instance of another entity TERM 34 time stamp DEFINITION 34 time value that is associated with a data value, often indicating when some event occurred that affected the data value
