Methods and systems for model matching

Abstract

Systems and methods for automatically and generically matching models are provided, such as may be provided in a matching application or matching component, or provided in a general purpose system for managing models. The methods are generic since the methods apply to hierarchical data sets outside of any particular data model or application. Similarity coefficients are calculated for, and mappings are discovered between, schema elements based on their names, data types, constraints, and schema structure, using a broad set of techniques. Some of these techniques include the integrated use of linguistic and structural matching, context dependent matching of shared types, and a bias toward subtree, or leaf, structure where much of the schema content resides.

Description

COPYRIGHT NOTICE AND PERMISSION A portion of the disclosure of this patent document may contain material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the. Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever. The following notice shall apply to this document Copyright ® 2001, Microsoft Corporation. FIELD OF THE INVENTION The present invention relates to model or schema matching, or more generally to the matching of separate hierarchical data sets. More particularly, the present invention relates to methods and systems for matching models, or schemas, that discover similarity coefficients between schema elements, including analyses based on one or more of schema names, schema data types, schema constraints and schema structure. BACKGROUND OF THE INVENTION Match is a schema manipulation oper...

AI Technical Summary

Problems solved by technology

Schema matching is challenging for many reasons.

Also, there is a related problem of query discovery, which operates on mapping expressions to obtain queries for actual data translation.

Each is a rich and complex problem that deserves independent study.

It is recognized that the problem of schema matching is inherently subjective.

Schemas may not completely capture the semantics of the data they describe, and there may be several plausible mappings between two schemas, making the concept of a single best mapping ill defined.

Thus, the goal of schema matching and one not yet adequately achieved by today's algorithms is: Given two input schemas in any data model, optional auxiliary information and an input mapping, compute a mapping between schema elements of the two input schemas that passes user validation.

However, each of the above solutions does not provide an adequate solution to the generic problem of matching schemas.

While some of the above solutions may be adequate for a given matching task, due to a design for the particular task, the solution is not a general all purpose approach to model matching.

Others were not designed for matching per se, but rather were designed for some other purpose such as schema integration, and thus the techniques applied to matching for these solutions make compromises that do not generalize adequately.

Still other existing algorithms are too slow on today's hardware for interactive use, as a result of exhaustive calculations and the like.

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