Answer to Exercise ER-7
- The minimum number of Cs that can be associated with one A is 1. I know this because the existence of the C to A relationship is mandatory. The maximum number of Cs that can be associated with one A is unlimited (or many). I know this because the cardinality of the C to A relationship is 1-M.
- Answers
- This is consistent with the diagram since Mackenzie is managing one project. A person must manage at least one project.
- This is consistent with the diagram since Lindsey is managing two projects. A person must manage at least one project with no upper limit.
- This is inconsistent with the diagram. The diagram states that a person must manage at least one project and Joe does not manage any.
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