Dissipating with Relations: Implication for the Entity-Relationship Model
This addresses foundational issues in conceptual modeling for database design, but it is incremental as it builds on existing models.
The paper tackles the problem of ontological ambiguity in the relationship construct of the Entity-Relationship (ER) model by re-casting ER diagrams using the thinging machine (TM) model, showing that relationships dissipate into flows and events in TM.
Difficulties arise when conceptual modeling lacks ontological clarity and rigorous definitions, which is especially the case in the relationship construct. Evidence shows that use of relationships is often problematic when it comes to communicating the form of meaning of an application domain. Research on this topic is important because relationships are central to a number of approaches and commonly used by practitioners. In this paper, we study the notion of relation or relationship in the context of conceptual modeling. Specifically, we focus on the notion of relationship used in the entity-relationship (ER) model. The ER model is scrutinized through a new form of conceptual modeling called the thinging machine (TM) to pursue further understanding of the semantics of the relationship concept. The ER model is composed of three fundamental categories (i.e., entity, relationship and attribute), whereas TM is built from one ontological category called the thing/machine (thimac). Several ER diagrams are re-casted as TM diagrams, creating a categorical collision with interesting implications regarding the status of the conception of relationship in a conceptual model. The re-modeling shows that the relational construct is dissipated into TM flows of things and chronology of events.