Schema Integration and Query Processing for Multiple Object Databases

Arbee L.P. Chen*, Jia Ling Koh, Tony C.T. Kuo, Chih Chin Liu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


In a multiple database system, a global schema created by integrating schemas of the component databases provides a uniform interface and high level location transparency for the users to retrieve data. The main problem for constructing a global schema is to resolve conflicts among component schemas. In this paper, we define corresponding assertions for the database administrators to specify the semantic correspondences among component object schemas. Based on these assertions, integration rules are designed, which use a set of primitive integration operators to restructure the component schemas for resolving the conflicts and do the integration. The principle of our integration strategy is to keep the data of component databases retrievable from the global schema without losing information. Moreover, more informative query answers may be derived from the multiple databases due to schema integration. The strategies for processing the global queries are proposed, which use the provided mapping information between global schema and component schemas to decompose the global queries into a set of subqueries. A Flow Control Language is then defined to specify the execution flow of the subqueries as well as the integration of the partial results. Some query optimization techniques are considered in the specification of the execution flow.

Original languageEnglish
Pages (from-to)21-34
Number of pages14
JournalIntegrated Computer-Aided Engineering
Issue number1
Publication statusPublished - 1995
Externally publishedYes

ASJC Scopus subject areas

  • Software
  • Theoretical Computer Science
  • Computer Science Applications
  • Computational Theory and Mathematics
  • Artificial Intelligence


Dive into the research topics of 'Schema Integration and Query Processing for Multiple Object Databases'. Together they form a unique fingerprint.

Cite this