On Modeling Closed Entity-Relationship Diagrams in an Elementary Mathematical Data Model
نویسنده
چکیده
Introduced are the concepts of closed entity-relationship diagrams (CERDs), and of partially, and generalized commutative diagrams (which are particular types of CERDs). Briefly presented is the elementary mathematical data model (EMDM), used to enable more accurate database scheme design. Provided is an algorithm for assisting database designers in modeling CERDs. Shown is that every such CERD should be thoroughly scrutinized according to this algorithm, even if some of them might prove ”uninteresting” in the end.
منابع مشابه
MASTER OF SCIENCE Computational Mathematics and Modern Information Technologies
Entity-Relationship Data Model: Data structuring, Entity-Relationship Diagrams, Equivalence of EntityRelationship and the Functional Modeling, Algorithms for translating Entity-Relationship Diagrams into Relational and Elementary Mathematical Data Models. Relational Data Model: The structure of the Relational Data Model, Relational Algebra, Relational Calculus, Relational Query Languages, Stati...
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