• Title/Summary/Keyword: Cardinality Operator

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An Efficient Schema Extracting Technique Using DTD in XML Documents (DTD를 이용한 XML문서의 효율적인 스키마 추출 기법)

  • Ahn, Sung-Eun;Choi, Hwang-Kyu
    • Journal of Industrial Technology
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    • v.21 no.A
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    • pp.141-146
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    • 2001
  • XML is fast emerging as the dominant standard to represent and exchange data in the Web. As the amount of data available in the Web has increased dramatically in recent years, the data resides in different forms ranging from semi-structured data to highly structured data in relational database. As semi-structured data will be represented by XML, XML will increase the ability of semi-structured data. In this paper, we propose an idea for extracting schema in XML document using DTD.

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A Transformation Technique of XML DTD to Relational Database Schema Based On Extracting Common Structure in XML Documents (공통 문서 구조 추출을 통한 XML DTD의 관계형 데이터 베이스 스키마 변환 기법)

  • Ahn, Sung-Eun;Choi, Hwang-Kyu
    • The KIPS Transactions:PartD
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    • v.9D no.6
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    • pp.999-1008
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    • 2002
  • XML is emerging as a standard data format to exchange and to present data on the Web. There are increasing needs to efficiently store and to query XML data. In this paper. we propose a new schema transformation algorithm based on a common structure extracting technique from XML documents. The common structure is shared by all XML documents referenced by DTD and the uncommon structure is ununiformly appeared on all XML documents referenced by DTD. Based on the extracted common and uncommon structures, we transform XML DTD into relational database schema. We conduct a performance evaluation based on the number of the generated tables, the size of the record, query processing time and the number of joins on the query. The performance of our algorithm is compared with the existing algorithms, then in most cates, our algorithm is better than the existing ones with respect to the number of the generated tables and appearance of NULL values in the tables.