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Query Algebra for the Very Loosely Structured Data Model
Ying Pan,Changan Yuan,Zhengqi Li,Wenjing Li 보안공학연구지원센터 2015 International Journal of Database Theory and Appli Vol.8 No.1
In order to realize the idea of pay-as-you-go (PAYG) data management which dataspace emphasizes, the very loosely structured data model is usually used to describe the massive, heterogeneous and dynamic data in dataspace. However, the present study mainly concentrates on the applications of the data model, and the query theory research is less. The query algebra is a theoretical foundation for query and its optimization in a PAYG fashion, so that how to establish a complete algebra based on the characteristics of loosely structured data model is an important problem need to be solved. In this paper, a formal definition of very loosely structured data model is given, then the query model and query algebra based on the model are proposed, which support to not only the operations such as set operators, selection, projection and join, but also association query in dataspace.