Figure 4 14 Example of mapping a binary 11 relationship b Resulting relations

Figure 4 14 example of mapping a binary 11

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Figure 4-14 Example of mapping a binary 1:1 relationship b) Resulting relations Transforming EER Diagrams into Relations: Binary Relationships Foreign key goes in the relation on the optional side, matching the primary key on the mandatory side
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Agenda Relational Model Definition Integrity Constraints Transforming EER Diagrams into Relations Entities Binary Relationship Associative Entities Other Relationships Normalization Denormalization and Partitioning Data
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Transforming EER Diagrams into Relations: Associative Entities Mapping Associative Entities Identifier Not Assigned Default primary key for the association relation is composed of the primary keys of the two entities (as in M:N relationship) Identifier Assigned It is natural and familiar to end - users Default identifier may not be unique
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Figure 4-15 Example of mapping an associative entity a) An associative entity Transforming EER Diagrams into Relations: Associative Entities Identifier NOT Assigned
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Figure 4-15 Example of mapping an associative entity (cont.) b) Three resulting relations Composite primary key formed from the two foreign keys Transforming EER Diagrams into Relations: Associative Entities
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