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M:N relationships

19 十月, 2015 - 15:13

Mapping M-N Binary Relationship Type: For each M-N Binary Relationship, identify two relations A, B represent two entity type participating in R. Create a new relation S to represent R. Include in S as foreign keys the primary keys of A and B and all the simple attributes of R. The combination of primary keys of A and B will make the primary key of S.