【摘要】 为解决目前农村地表水质数据交换中存在的问题,考虑使用上级结点主动从下级结点处提取的方式获取数据,提出了上层控制权的思想。通过上级结点直接控制访问下级结点数据库的形式,建立数据交换模型,利用XML进行目标数据库字段到本地数据库字段的映射,构建通用的数据库查询语句自动生成系统,提取所需数据,实现异构数据库之间数据的无缝交换。更多还原

【Abstract】 In oder to solve the problems in rural surface water data exchange,it was considered that the parent node obtained the data from the sub-node,and the higher domination concept was proposed.Through the direct access of parent node to the database of sub-node,the data exchange mode was constructed,and then the mapping from target fields to local fields was realized by using XML,at last an automatic generation system for common database query was built to extract data and achieve the seamless exchange of data between the heterogeneous databases.更多还原