%0 Journal Article
%T A Data Model and Algebra for Object Integration Based on a Rooted Connected Directed Graph<br>基于带根连通有向图的对象集成模型及代数
%A WANG Ning
%A XU Hong-bing
%A WANG Neng-bin
%A <br>王　宁
%A 徐宏炳
%A 王能斌
%J 软件学报
%D 1998
%I 
%X A data model named OIM is proposed in this paper as the common data model for integration of heterogeneous data sources. Based on rooted connected directed graph both cyclic and acyclic, OIM can describe the relationship of a complex object and its component objects, as well as the links between HTML files in World-Wide-Web naturally. As the metadata is associated with each object, OIM is especially suitable for describing objects without explicit predictable data schemata. As the formal foundation for query decomposition and optimization, a new algebra called OIM algebra, which includes six operations, i.e., object union, difference, select, project, paste and cut, is proposed. In comparison with relational algebra, OIM algebra is more flexible and powerful.
%K Heterogeneous data sources
%K semi-structured data
%K data integration
%K data model
%K object algebra<br>异构数据源，半结构化数据，数据集成，对象模型，对象代数.
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=5B3AB970F71A803DEACDC0559115BFCF0A068CD97DD29835&cid=8240383F08CE46C8B05036380D75B607&jid=7735F413D429542E610B3D6AC0D5EC59&aid=6CB6B9DC7AE4C5144C8D9D7172B5023E&yid=8CAA3A429E3EA654&vid=9CF7A0430CBB2DFD&iid=59906B3B2830C2C5&sid=117143DBED3B4430&eid=9124D83E61CF1CD0&journal_id=1000-9825&journal_name=软件学报&referenced_num=22&reference_num=10