Storage schema is a key research field in the community of XML data management. About the performance,expressions of the underlying storage have very important effects on the top queries and optimizations. Therefore,effectively building the storage schema of the XML is the primary problem. This paper proposed an edge-mapping XML document storage schema, which effectively maps the XML database onto relational database. In this schema: firstly, the XML document tree was structured according to the type of the document node. Secondly, a union-table was used to store the value of nodes, and we only recorded the path of the element nodes by the mean of the node sequence number combined with the path. Finally, based on this storage schema, we implemented the database operations on the new database model. Experiments showed that the model can speed up the query procedures and can spare more memory space.%存储方案是XML数据管理研究领域的核心问题之一.底层的存储表达在性能上对上层的查询和优化有着重要的影响,因此有效地建立XML文档的存储方案是首要问题.以关系数据库为基础,提出了一种基于边模型映射的XML存储方案的数据库模型.在该模型中,首先依据文档中的结点类型对XML文档树进行结构细化;其次采用联合表来存储结点的值,并在该表中采用结点序号和路径相结合的方式,仅记录每一个元素结点的路径;最后在这种新的存储模式的基础上,实现了针对该模型的数据库操作.实验表明,该模型在查询速度和存储空间方面较以往的工作都有明显的改善.
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