This is a case of what's called "generalization/specialization" in ER lingo. So, how can I represent accurately this sort of relationship in my diagram? Each attribute in EMPLOYEE applies to MANAGER and DRIVER, but MANAGER and DRIVER will have some extra attributes that are not characteristics of the EMPLOYEE entity type (or table, once it is implemented). I am new to this, so I am not sure whether I have to type out all the attributes 1 again in the subclass entities (or subtypes), i.e., MANAGER and DRIVER, or whether I there is a way of connecting to and grabbing the attributes from the superclass (or supertype) so that it is more clear that they relate, something like a FOREIGN KEY, I guess.ġ. I am trying to figure out how to represent a one-to-one (1:1) relationship regarding a superclass/subclass or supertype-subtype structure in an entity-relationship diagram (ERD) of the kind created by means of MySQL Workbench (which, as you know, looks more close to a concrete SQL implementation than an original P. Representing a Superclass/Subclass (or Supertype-Subtype) relationship in a MySQL Workbench diagram
Mysql database-design erd database-diagrams subtypes
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