For the relationship represented in the figure, which of the following is true?

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BlackTom AI · Accepted Answer

Question: For the relationship represented in the figure, which of the following is true?

Option 1: A department must have a least one employee.
- Why it’s not correct: The diagram shows an optional participation at the Employee side of the Works In relationship (the small circle near Employee), which indicates that an Employee may exist without being related to a Department. This means a Department is not forced to have at least one employee in every instance of the relationship.

Option 2: A department can have more than one employee.
- Why it’s not correct: The visual notation here does not clearly indicate multiple employees per department in this particular schema. Depending on the exact cardinality symbol (e.g., a crow’s foot near Department), this might be misread, but the provided correct answer emphasizes that the important, unambiguous takeaway from the diagram is about the Employee side’s optional participation and potential for linkage to multiple departments, not a guaranteed multiple employees per department.

Option 3: An employee can work in more than one department but does not have to work for any department.
- Why it’s correct: The key clues are the optional participation near the Employee entity (the circle) and the way the relationship line is drawn between Employee and Department. The optional circle indicates an Employee is not required to be in the relationship (i.e., may work in zero departments). The structure of the line suggests the possibility of an Employee being related to more than one Department (i.e., an employee can work in multiple departments). Therefore, an Employee can be in zero, one, or multiple departments, depending on the instance.

Option 4: An employee has to work for more than one department.
- Why it’s not correct: This statement demands that every Employee participate in more than one Department. The diagram shows optional participation and does not enforce multiple departmental work assignments for every Employee. Therefore, this is too strong a requirement to infer from the given notation.

In summary, the only statement that aligns with the diagram’s implied optional participation and potential multi-department membership for an individual Employee is option 3.

For the relationship represented in the figure, which of the following is true?

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