The most recognizable characteristic of crow’s foot notation (also known as IE notation) is that it uses graphical symbols to indicate the ‘many’ side of the relationship. The three-pronged ‘many’ symbol is also how this widely-used notation style got its name. Let’s see where crow’s foot is placed in the history of data modeling and take a look at its symbols. History: How Crow’s Foot Notation Got Started The beginning of crow’s foot notation dates back to an article by Gordon Everest (1976, Fifth Computing Conference, IEEE).
Various ERD notations follow different styles for entities, relationships, and attributes. Usually there isn’t much standardization between them, so notations bear little resemblance to each other. Among the plethora of ERD diagram notations, crow’s foot notation is definitely the most used. In this article, we’ll investigate its components within the Vertabelo database model. Before we start looking into crow’s foot notation, we must understand that there are various levels of Entity-Relationship diagrams: conceptual data model – an overview of what should be included in the general database model.