Entity-relationship
An entity-relationship model (ERM) is an abstract and conceptual representation of data, information aspects of a business domain or its process requirements
Erd
Entity Relationship Diagram (ERD) or Entity Relationship Model is a visual representation of the organization of data within databases or information systems
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Normalization is normally done after a conceptual erd is translated to a logical relational model not directly on an erd or in the process of creating one;understanding how entity sets attributes and relationships translate to domains relations and dependencies may invite one to try normalizing directly in the erd but a problem with this approach is that the entity-relationship model isn t a complete and consistent logical model and so some relations may not be representable in an erd from question Is this ERD correct and how to do normalization? |
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Entity-relationship modelers can picture this in an erd using a figure for generalization and specialization;but entity-relationship modeling doesn t tell you how to build the tables from question How to model this context that has custom form fields |
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First entity-relationship modeling is more than just an erd from question Why is a specific cardinality not allowed in the ERD? |