ITPEC FE Subject A April 2024 Question 19

Many employees per department, and possibly several dependents per employee — in this notation an arrow points from the "one" side to the "many" side.

• •Department → Employee: one department has many employees, and each employee belongs to one department
• •Employee → Dependent: one employee can have many dependents, and each dependent belongs to one employee

Answer (a)

Why not others:

• •(b) — "exactly one dependent" makes Employee to Dependent one-to-one, but the arrow marks one-to-many
• •(c) — "at most one dependent" caps the many side at one, which the arrow does not
• •(d) — the relationship is one-to-many from Department, so each employee belongs to exactly one department; working in two would need many-to-many

Key rule: Read each relationship in both directions (one department has many employees, each employee has one department) and check a statement against the cardinality at the end it describes.

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