Database Schema Transformation & Optimization
نویسنده
چکیده
An application structure is best modeled first as a conceptual schema, and then mapped to an internal schema for the target DBMS. Different but equivalent conceptual schemas often map to different internal schemas, so performance may be improved by applying conceptual transformations prior to the standard mapping. This paper discusses recent advances in the theory of schema transformation and optimization within the framework of ORM (Object-Role Modeling). New aspects include object relativity, complex types, a high level transformation language and update distributivity.
منابع مشابه
Electronic Communications of the EASST
Most processes in database engineering consist in transforming schemas according to definite requirements. Basically, a schema transformation is a rewriting rule that allows schema constructs to be replaced by other constructs that are expected to better meet these requirements. Schema normalization, logical design, schema integration, view derivation, proving schema equivalence, data conversio...
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