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ER Modeling: Entities, Attributes, Relationships and Crow's Foot Notation

ER modeling draws data as entities, attributes and relationships; describing a relationship correctly takes both the maximum (cardinality) and the minimum (optionality) at each end. We cover simple, composite, multivalued and derived attributes, unary, binary and ternary relationships, the Chen and Crow's Foot notations, the Bookstore's Mermaid erDiagram draft, and what is lost when you generate a diagram from SQL Server's catalog views.