Single line with an arrow mark in Entity Relattionship diagram

er-diagrams entity-relationship
starthree picture starthree · Jan 21, 2011 · Viewed 28.6k times · Source

What do single line with an arrow mark in ER diagram represent?

Answer

py2020 picture py2020 · Jan 21, 2011

As per Bachman Notation which you are using ,

"For every relation a rectangle has to be drawn and every coupling is illustrated by a line that connects the relations. On the edge of each line arrows indicate the cardinality. We have 1-to-n, 1-to-1 and n-to-m"

And "Cardinality use to represent the relationship between two entities."

For more on cardinality Notations alt text

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