对象代理数据库的虚属性查询优化方法

来源 :2014全国理论计算机科学学术年会 | 被引量 : 0次 | 上传用户:helen_00_00
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为对象代理数据库的虚属性查询提出两种优化方法——表达式提升和虚属性合并.表达式提升将虚属性查询转换为对源类中实属性的查询;虚属性合并是对查询涉及的属于相同源对象的多个虚属性,一次性获取相应源对象的属性值用于虚属性值的计算,避免多次访问同一源对象.通过实验分析了这两种方案对虚属性查询的性能影响,实验结果表明,对于虚属性和代理层数较多的查询,表达式提升和虚属性合并的方法极大提升了查询效率.
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