Entity vs. Relationship

• First ER diagram OK if a manager gets a separate discretionary budget for each dept.

• What if a manager gets a discretionary budget that covers all managed depts?

  • Redundancy of dbudget, which is stored for each dept managed by the manager.

Manages2

name

dname

budget

did

Employees

Departments

ssn

lot

dbudget

since

Misleading: suggests dbudget

tied to managed dept.

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