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Many-to-many (data model)

Systems analysis concept / From Wikipedia, the free encyclopedia

In systems analysis, a many-to-many relationship is a type of cardinality that refers to the relationship between two entities,[1] say, A and B, where A may contain a parent instance for which there are many children in B and vice versa.

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An Author can write several Books, and a Book can be written by several Authors
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The Author-Book many-to-many relationship as a pair of one-to-many relationships with a junction table