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Entity/Relationship Modelling, Database Design, Entities, Attributes, Relationships, Constraints on Relationships, Extended E/R Modelling, Entity Set, Key Attributes, Relationship Type, Relationships in E/R, Relationship Attributes, N-ary Relationships, Recursive Relationships, Cardinality, Cardinality Ratios, Participation Constraints, Weak Entity, Weak Entity Types, ISA Hierarchies, Attribute Inheritance, Aggregation, Data Model, European Bioinformatics Institute
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Lecture 2: Entity/Relationship modelling
www.cl.cam.ac.uk/Teaching/current/Databases/
Dr. Peter Chen http://bit.csc.lsu.edu/~chen/
Today
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Employees
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Employees
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name (^) dob
supervisor subordinate
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Manages
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Employees
DID dname budget
Department
since
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