Abstract
While the schema-less feature of the OEM (Object Exchange Model) gives flexibility in representing semi-structured data, it brings difficulty in formulating database queries. Extracting schema from an OEM database then becomes an important research topic. This paper presents a new approach to this topic with the following features. (1) In addition to representing the nested label structure of an OEM database, the proposed OEM schema keeps up-to-date information about instance objects of the database. The object-level information is useful in speeding up query evaluation. (2) The OEM schema is explicitly represented as a label-set, which is easy to construct and update. (3) The OEM schema of a database is statically built and dynamically updated. The time complexity of building the OEM schema is linear in the size of the OEM database. (4) The approach is applicable to a wide range of areas where the underlying schema is much smaller than the database itself (e.g. data warehouses that are made from a set of heterogeneous databases).
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Project partly supported by the National Natural Science Foundation of China.
Shen Yidong is a Professor of computer science at Chongqing University. He received his Ph.D. degree in computer science from Chongqing University in 1991. He was a visiting researcher at the University of Valenciennes, France (1992–1993) and the University of Maryland Institute for Advanced Computer Studies, USA (1995–1996), respectively. His research interests include artificial intelligence, deductive and object-oriented databases, logic programming and parallel processing.
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Shen, Y. Extracting schema from an OEM database. J. of Comput. Sci. & Technol. 13, 289–299 (1998). https://doi.org/10.1007/BF02946619
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DOI: https://doi.org/10.1007/BF02946619