These are shown on both sides of the line. In the Entity-Relationship model, representing a ternary or higher order of relationship is problematic. Note that the mentioned type of relationship is binary. This describes what kind of relationship connects the objects. Usually, each relationship has a name, expressed as a verb, written on the relationship line. Relationships illustrate the association between two entities. Let’s now take a look at the representation of entities and relationships in crow’s foot notation. Showing that an individual X can relate to multiple Ys (and each Y relates to at most one X). I like the fork since it can easily be represented in a standard character set as in: The use of the notation was incidental though carefully chosen. In my original paper, the focus was on “Basic data structures explained with a common example” ² (the title, which later became chapter 4 in my McGraw Hill text, Database Management, 1986). I now prefer to call it a FORK, which is short and to the point, and doesn’t require the possessive crow’s or the longer chicken. Others then started referring to it as chicken feet (e.g., Carlis textbook ¹). I prefered it to the arrow because it did not imply directionality or a physical access path, and it was visually intuitive, showing manyness. I called it the “inverted arrow.” at the time to distinguish from Bachman’s notation.
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