Differences between EER and UML

问题:

I'm putting together a visual representation of a database I designed.

I've downloaded MySQL workbench and can create a EER diagram.

What's the difference between this and a UML diagram?

Also, where does a ERD come into this?

I can't find a question on here that matches what I'm after here?

Thanks.

回答1:

I think by UML diagram you mean : UML Class Diagram. [ there are other UML diagrams also]

EER (Enhanced entity–relationship) Diagram-Model

Used for Database Design. Like class diagrams support also subclass -superclass [specialization and generalization]. So entities in EER diagrams has attributes not methods.Because they show just plain data.

Note: ER [entity–relationship] Diagrams are origin of EER. They are from Structured Analysis. Also used for database modeling.How ER become to EER? I think because of Object Oriented Style Hype.

UML Class Diagrams

Used for Object Oriented Analysis-Design.

Can be used to model databases also : there are UML class profiles for it. [I think UML profiles for Database Designs are NOT good as ER diagrams]

But in simple terms classes are blueprints in which objects instantinated . So classes may have methods-functions as well as attributes.Software classes definitely has methods but conceptual classes[ used for domain modeling] may not.