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Identifying Extended Entity-Relationship Object Structures in Relational Schemas
August 1990 (vol. 16 no. 8)
pp. 777-790

Relational schemas consisting of relation-schemes, key dependencies and key-based inclusion dependencies (referential integrity constraints) are considered. Schemas of this form are said to be entity-relationship (EER)-convertible if they can be associated with an EER schema. A procedure that determines whether a relational schema is EER-convertible is developed. A normal form is proposed for relational schemas representing EER object structures. For EER-convertible relational schemas, the corresponding normalization procedure is presented. The procedures can be used for analyzing the semantics of existing relational databases and for converting relational database schemas into object-oriented database schemas.

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Index Terms:
extended entity-relationship object structures; relation-schemes; key dependencies; key-based inclusion dependencies; referential integrity constraints; EER schema; EER-convertible; normal form; relational schemas; EER object structures; normalization procedure; semantics; relational database schemas; object-oriented database schemas; database management systems; database theory; object-oriented programming; relational databases.
V.M. Markowitz, J.A. Makowsky, "Identifying Extended Entity-Relationship Object Structures in Relational Schemas," IEEE Transactions on Software Engineering, vol. 16, no. 8, pp. 777-790, Aug. 1990, doi:10.1109/32.57618
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