Entity Relationship Model
We are missing two entity relationships in the crows foot notation.
(1) 1 to many (with at least one required, i.e. (1..n)). Your notation supports 1 to (0 .. n)
(2) 1 to zero or one (0..1)
4
votes
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Dzmitry Hryb commented
1..* exists in 2.5 version