Querying Schema Information
نویسندگان
چکیده
Schema queries can play an important role while retrieving information from multiple sources, for example, in query formulation and in query optimization. We identify four classes of schema queries that we have found useful while designing an application programming interface for frame representation systems (FRSs): taxonomic, frame structure, constraint and class comparison queries. We propose a scheme for direct support for these queries in a mediator language such as Object Query Language (OQL).
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تاریخ انتشار 1997