icemountain talks about cardinality in ER diagrams. He suggests that you may sometimes want to use specific numbers instead of 0, 1, or many. He has a point.
You can think of many occasions where you might want a specific number. For instance, you need a minimum of 9 baseball players for a team.
However, to figure out the number of tables, this level of detail just adds complexity without real benefit. To determine the tables you need beyond the entities specified, you need to know whether relationships are many-to-many or not. Therefore, I am just asking that you be precise to the many, 0, or 1 level.
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