Object–role modeling: Difference between revisions

Revision as of 19:59, 6 November 2021

Revision as of 20:35, 14 March 2022

Line 1:

{{Distinguish|object–relational mapping}}

{{short description|Programming technique}}

{{Distinguish|object–relational mapping}}

[[File:ORM-diagram-tkz-orm.png|406px|thumb|Example of an ORM2 diagram]]

Line 32:

Object-role models are based on elementary facts, and expressed in [[diagram]]s that can be verbalised into natural language. A fact is a [[proposition]] such as "John Smith was hired on 5 January 1995" or "Mary Jones was hired on 3 March 2010".

With ORM, [[proposition]]s such as these, are abstracted into "fact types" for example "Person was hired on Date" and the individual propositions are regarded as sample data. The difference between a "fact" and an "elementary fact" is that an elementary fact cannot be simplified without loss of meaning. This "fact-based" approach facilitates modeling, transforming, and querying information from any ___domain.<ref name="orm.net">http://www.orm.net/pdf/ORM2_TechReport1.pdf {{Bare URL PDF|date=March 2022}}</ref>

=== Attribute-free ===

Line 67:

* [[Concept map]]

* [[Conceptual schema]]

* [[Enhanced entity–relationship model| EER (Enhanced entity–relationship model)]]

* [[Information flow diagram]]

* [[Ontology double articulation]]