CSCI 403: Databases 9 - Relational Database Design and Entity-Relationship Diagrams
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چکیده
The three main components of an ERD are the entities, attributes, and relationships. Entities things or objects with independent existence, such as persons, products, companies, courses. Entities are the nouns of the ERD. Attributes the properties describing an entity. Relationships the way entities interact or refer to each other. Relationships are the verbs of the ERD. For example, a person supervises a department, an instructor teaches a course, a person works on a project.
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MASTER OF SCIENCE Computational Mathematics and Modern Information Technologies
Entity-Relationship Data Model: Data structuring, Entity-Relationship Diagrams, Equivalence of EntityRelationship and the Functional Modeling, Algorithms for translating Entity-Relationship Diagrams into Relational and Elementary Mathematical Data Models. Relational Data Model: The structure of the Relational Data Model, Relational Algebra, Relational Calculus, Relational Query Languages, Stati...
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