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公开(公告)号：US06421658B1
公开(公告)日：2002-07-16
申请号：US09365590
申请日：1999-07-30
IPC分类号： G06F1730
CPC分类号： G06F17/30595 , Y10S707/99931 , Y10S707/99932 , Y10S707/99933 , Y10S707/99935 , Y10S707/99945
摘要： A method for typed view hierarchies for an object-relational database management (OPDBMS). The views in the hierarchy are merged into a unified hierarchy view through case expressions for mapping and wrapping of overloaded columns. During the merge, the underlying logical tables are eliminated which results in a simplified query graph. The transformation is a non-loss operation which condenses the type information within the case expressions. This allows update, delete and insert operations to be resolved on the query graph on a local level. Using query rewrite rules, the case expressions may be simplified further.
摘要翻译： 用于对象关系数据库管理（OPDBMS）的类型化视图层次结构的方法。 层次结构中的视图通过用于映射和包装重载列的案例表达式合并到统一层次结构视图中。 在合并期间，消除了基础逻辑表，从而产生简化的查询图。 该转换是一种非损失操作，它将表达式中的类型信息进行聚合。 这允许在本地级别的查询图上解决更新，删除和插入操作。 使用查询重写规则，可以进一步简化案例表达。
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公开(公告)号：US06728952B1
公开(公告)日：2004-04-27
申请号：US09405884
申请日：1999-09-24
IPC分类号： G06F945
摘要： A computer system identifies a predicate in a computer language containing constant expressions as vacuous. The system identifies distinct variables contained in the predicate and represents the predicate by a set of bounding rectangles. The bounding rectangles are represented in a space having a number of dimensions equal to the number of variables. There are finite limits on dimensions of a bounding rectangle which represent the relationship between the variables in the predicate and the constant expressions in the predicate. The predicate is identified as vacuously FALSE where the set of bounding rectangles is empty.
摘要翻译： 计算机系统将包含常数表达式的计算机语言的谓词识别为空虚。 系统识别谓词中包含的不同变量，并通过一组边界矩形表示谓词。 边界矩形在具有等于变量数量的维数的空间中表示。 对于表示谓词中的变量与谓词中的常量表达式之间的关系的边界矩形的维度有限制。 该谓词被识别为空虚FALSE，其中一组边界矩形为空。
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