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EER: Enhanced E-R Model

EER: Enhanced E-R Model. Specialization / Generalization SubClass / SuperClass. Subclasses for Different Roles. SuperClass: Staff SubClasses: Manager SalesPersonnel Secretary. Common and Different Attributes. SuperClass:

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EER: Enhanced E-R Model

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  1. EER: Enhanced E-R Model Specialization / Generalization SubClass / SuperClass

  2. Subclasses for Different Roles SuperClass: Staff SubClasses: Manager SalesPersonnel Secretary

  3. Common and Different Attributes SuperClass: Staff: staffNo, name, address, phone, salary SubClasses: Manager: mgrStartDate, bonus SalesPersonnel: salesArea, carAllowance Secretary: typingSpeed

  4. Different Entities for Subclasses?

  5. Constraints for Sub-Classes Participation: Mandatory Optional Disjoint: Disjoint (or) Non-disjoint (and) Business Rules

  6. Participation: Mandatory SuperClass: Staff SubClasses PartTime FullTime

  7. Participation: Optional SuperClass: Staff SubClasses Supervisor Supervisee

  8. Disjoint (Xor) SuperClass: Staff SubClasses PartTime FullTime

  9. Nondisjoint (And) SuperClass: Staff SubClasses: Manager SalesPersonnel Secretary

  10. Staff staffNo Manager bonus Secretary typingSpeed SalesPersonnel salesArea EER Diagram {Mandatory, And}

  11. Staff staffNo FullTime salaryScale PartTime hoursRate EER Diagram {Mandatory, Xor}

  12. EER is Optional for Assignment 3

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