I'm taking a Database course and I'm a bit confused with the different types of graphical representations terminology of a database design. Are Data Model, Crows Foot Notation, Crows Foot Model, ERD & ERM all the same. Where do they differ?
My understanding is as follows:
-Crows Foot Notation - Graphically illustrate the relationship (ex. zero or many, one or many, one and only one, zero or one)between two or more entities.
-Crows Foot Model - Is this the same as Crow's Foot Notation?
-ERD - Illustrate each entities name, attributes and keys. Do I need to display the dataypes as well? Does this also consist of the Crows Foot notation?
-ERM - Is this the same as ERD.
-Data Model - I assume this is very general. Would this consist of an illustration of the entities and its name and arrows pointing to the entities it relates to?