Titlebook: Entity-Relationship Approach - ER ‘92; 11th International C G. Pernul,AM. Tjoa Conference proceedings 1992 Springer-Verlag Berlin Heidelber

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Incompetent

Carrier Transmission of Signals,e is stepwise so that clustered designs on different levels are achieved. Parenthood connections are used to build increasingly complex entity sets out of primitive ones. No semantical extensions of the original ER model are necessary because these connections are identified by their cardinalities alone.

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brachial-plexus

,Entity tree clustering — A method for simplifying ER designs,e is stepwise so that clustered designs on different levels are achieved. Parenthood connections are used to build increasingly complex entity sets out of primitive ones. No semantical extensions of the original ER model are necessary because these connections are identified by their cardinalities alone.

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The use of a lexicon to interpret ER diagrams: a LIKE project,, relationships, attributes, values, actors, messages, etc. Usually these words have a certain meaning and usually their usage is according to that meaning. In this paper we will describe how a Lexicon, containing these words and their meaning, can be used fruitfully when combined with a CASE tool.

Robust

Transforming conceptual data models into an object model,ived mainly from an extended Entity-Relationship approach, but concepts from other semantic and object-oriented models have influenced its features. It is shown how high-level conceptual data models can be mapped to this model, and to what extent the object model subsumes classical modeling paradigms.

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Fundamentals of cardinality constraints,omplete lifecycle of a database as an interface model. For this purpose, the concepts of the ER-model need to be theoretically wellfounded. The aim of this paper is to show how the theoretical basis of one of the most important class of integrity constraints can be constructed and then used for the

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Evaluation of complex cardinality constraints, is type-based, admits variants and detailed cardinality specifications, and can cope with incomplete intermediate states. Nevertheless, the resulting syntax is easy to understand..In this paper, an implementation of the valence concept is outlined. Special emphasis has been placed on minimizing spa