Is ERD considered a kind of UML diagram?

Question

Are Entity Relationship Diagrams(ERD's) considered a type of UML diagram or are they a separate thing?

question from:https://stackoverflow.com/questions/48191228/is-erd-considered-a-kind-of-uml-diagram

Answer 1

I have another idea. I think we should look in-depth.

When we are talking about ERD (Entity Relationship Diagram), we are talking about Entity Relationship Modeling.

It is firstly introduced by Peter Chen (1976). He has two famous articles on Entity Relationship Modeling (see first and second articles)

He talked about Entity-Relationship Modeling (not Entity-Relationship Diagram). It is ER Model.

There is another paper in 1975 about Modeling the Real World System.

ER Modeling is (see reference, the second paragraph):

In software engineering an ER model is commonly formed to represent things that a business needs to remember in order to perform business processes. Consequently, the ER model becomes an abstract data model that defines a data or information structure that can be implemented in a database, typically a relational database.

Diagramming Convention Techniques

When we are talking about ER Modeling, there many diagramming convention techniques.

1. Chen Notation (some links need translation)
2. IDEF1X Notation
3. Bechman Notation
4. Martin notation
5. (min, max)-notation of Jean-Raymond Abrial in 1974
6. UML class diagrams

And other notations (see reference)

All of above notations are using for ER Modeling or Data Modeling.

There is no earth-shattering difference between UML notation and other ER notations. They all model the most important elements of data models.

Finally: UML is a set of standard graphical tools to model the whole or parts of a project. We can use UML (Class Diagram) for ER Modeling and name them our ER Models or ERDs. So we can say: this is my ERD in UML Notation.