The Semantics of Reifying n-ary Relationships as Classes
نویسندگان
چکیده
Many data models do not directly support -ary relationships. In most cases, they are either reduced to some of their binary projections or directly translated into an -ary “relationship relation” in the relational model. This paper addresses the reification of an -ary relationship into a new class with binary relationships and studies the preservation of semantics in the translation. It shows that some semantics may be lost unless some explicit constraints are added to the binary schema.
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