Answer to Problem 3.2

To determine the cardinality for this relationship, I had to make several assumptions. Other assumptions are possible but I thought these seemed reasonable.

  • An employee can use the same skill on many projects.
  • An employee can use many skills on the same project.
  • Many employees use the same skill on the same project.

Given these assumptions, the cardinality for each entity type is M. So this is a M:M:M relationship.

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