• Title/Summary/Keyword: SQL Extension

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eMRA: Extension of MRA Considering the Relationships Between MDR Concepts (eMRA: MDR의 개념간 관계성을 고려한 MRA 확장)

  • Joo, Young-Min;Kim, Jangwon;Jeong, Dongwon;Baik, Doo-Kwon
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.3
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    • pp.161-172
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    • 2013
  • Metadata registry (MDR) is the international standard, developed by ISO/IEC for exchange and sharing data between databases. Many MDR systems are used in diverse domains such as medical service, bibliography, environment for sharing and integrating data. However, those systems have different physical structures individually because the MDR standard defines only the metamodel for registering and storing metadata. It causes heterogeneity between the system structures and requires additional cost to maintain interoperability. ISO/IEC 13249-8 Metadata Registry Access (MRA) is developing as an international standard to provide a consistent access facility to data stored in different metadata registries. However, MRA does not consider the relationships between the concepts (classes) defined in the MDR specification. It causes that incorrect query results returned from MDR systems. It also requires additional cost of modeling and rewriting queries to reflect each physical model. Therefore, this paper suggests eMRA which considers the relationships between the concepts in MDR. The comparative evaluations are described to show the advantages of eMRA. eMRA has superior performance in query modeling and referential integrity than MRA defined by the relationship between the concept of MDR.