公开(公告)号：US20030037056A1

公开(公告)日：2003-02-20

申请号：US10171728

申请日：2002-05-28

申请人： ORACLE CORPORATION

发明人： Eric Sedlar

IPC分类号： G06F007/00

CPC分类号： G06F17/30595 ,  Y10S707/99931 ,  Y10S707/99932 ,  Y10S707/99936 ,  Y10S707/99953

摘要： A method and mechanism are provided for creating, maintaining, and using a hierarchical index to efficiently access information in a relational system based on a pathnames, thus emulating a hierarchically organized system. Each item that has any children in the emulated hierarchical system has an index entry in the index. The index entries in the index are linked together in a way that reflects the hierarchical relationship between the items associated with the index entries. Pathname resolution is performed by following direct links between the index entries associated with the items in a pathname, according to the sequence of the filenames within the pathname. By using an index whose index entries are linked in this manner, the process of accessing the items based on their pathnames is significantly accelerated, and the number of disk accesses performed during that process is significantly reduced.

摘要翻译： 提供了一种用于创建，维护和使用分层索引的方法和机制，用于基于路径名有效地访问关系系统中的信息，从而模拟分层组织的系统。 在仿真分层系统中具有任何子节点的每个项目在索引中都有一个索引条目。 索引中的索引条目以反映与索引条目相关联的项目之间的层次关系的方式链接在一起。 根据路径名中的文件名的顺序，通过跟踪与路径名中的项目相关联的索引条目之间的直接链接来执行路径名解析。 通过使用其索引条目以这种方式链接的索引，基于其路径名访问项目的过程被显着加速，并且在该处理期间执行的磁盘访问的数量显着减少。

公开(公告)号：US20030065659A1

公开(公告)日：2003-04-03

申请号：US10260384

申请日：2002-09-27

申请人： ORACLE CORPORATION

发明人： Nipun Agarwal ,  Eric Sedlar ,  Ravi Murthy ,  Namit Jain

IPC分类号： G06F007/00

CPC分类号： G06F17/30595 ,  G06F17/30917 ,  Y10S707/99931 ,  Y10S707/99933 ,  Y10S707/99942 ,  Y10S707/99943 ,  Y10S707/99945

摘要： A hierarchy may be explicitly or implicitly reflected in existing data maintained external to hierarchy structures. Such hierarchies are referred to herein as a nullpre-existing hierarchiesnull. Techniques are described herein for capturing a pre-existing hierarchy in hierarchy structures. After a pre-existing hierarchy has been captured, there exist two independent sets of data that reflect the hierarchy: the external hierarchy definition and the internal hierarchy definition. Changing either hierarchy definition changes the hierarchy. Therefore, to maintain a consistent reflection of the hierarchy, the internal hierarchy definition must be modified in response to changes made to the external hierarchy definition, and the external hierarchy definition must be modified in response to changes made to the internal hierarchy definition. Various techniques are described for maintaining consistency between the two hierarchy definitions.

摘要翻译： 层次结构可以在层次结构外部维护的现有数据中显式或隐式地反映出来。 这样的层次结构在本文中称为“预先存在的层级”。 这里描述了用于在层次结构中捕获预先存在的层次结构的技术。 在捕获了一个预先存在的层次结构之后，存在反映层次结构的两个独立的数据集：外部层次结构定义和内部层次结构定义。 更改层次结构定义会更改层次结构。 因此，为了保持层次结构的一致反映，必须根据对外部层次结构定义所做的更改来修改内部层次结构定义，并且必须根据对内部层次结构定义的更改来修改外部层次结构定义。 描述了用于维持两个层次结构定义之间的一致性的各种技术。