公开(公告)号：US20140095520A1

公开(公告)日：2014-04-03

申请号：US13629907

申请日：2012-09-28

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Mohamed Ziauddin ,  Andrew Witkowski

IPC: G06F17/30

CPC classification number: G06F17/30492 ,  G06F17/30584 ,  G06F17/30592 ,  G06F17/30598

Abstract: Techniques are provided for generating a “dimensional zonemap” that allows a database server to avoid scanning disk blocks of a fact table based on filter predicates in a query that qualify one or more dimension tables. The zonemap divides the fact table into sets of contiguous disk blocks referred to as “zones”. For each zone, a minimum value and a maximum value for each of one or more “zoned” columns of the dimension tables is determined and maintained in the zonemap. For a query that contains a filter predicate on a zoned column, the predicate value can be compared to the minimum value and maximum value maintained for a zone for that zoned column to determine whether a scan of the disk blocks of the zone can be skipped.

Abstract translation: 提供了用于生成“维度zonemap”的技术，允许数据库服务器基于限定一个或多个维度表的查询中的过滤器谓词来扫描事实表的磁盘块。 zonemap将事实表划分为被称为“区域”的连续磁盘块的集合。 对于每个区域，维度表的一个或多个“分区”列中的每一个的最小值和最大值在zonemap中确定和维护。 对于在分区列上包含过滤谓词的查询，可以将谓词值与该分区列的区域维护的最小值和最大值进行比较，以确定是否可以跳过该区域的磁盘块扫描。

公开(公告)号：US20140095502A1

公开(公告)日：2014-04-03

申请号：US13629897

申请日：2012-09-28

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Mohamed Ziauddin ,  Andrew Witkowski

IPC: G06F17/30

CPC classification number: G06F17/30592 ,  G06F17/30289 ,  G06F17/30584 ,  G06F17/30598

Abstract: Techniques are provided that address the problems associated with prior approaches for clustering a fact table in a relational database management system. According to one aspect of the invention, a database server clusters a fact table in a database based on one or more dimension tables. More specifically, rows are stored in the fact table in a sorted order and the order in which the rows are sorted is based on values in one or more columns of one or more of the dimension tables. A user specifies the columns of the dimension tables on which the sorted order is based in “clustering criteria”. The database server uses the clustering criteria to automatically store the rows in the fact table in the sorted order in response to certain user-initiated database operations on the fact-table.

Abstract translation: 提供了解决与在关系数据库管理系统中聚类事实表的先前方法相关联的问题的技术。 根据本发明的一个方面，数据库服务器基于一个或多个维度表将数据库中的事实表聚类。 更具体地说，行以排序的顺序存储在事实表中，并且行被排序的顺序基于一个或多个维度表的一个或多个列中的值。 用户在“聚类标准”中指定排序顺序所基于的维度表的列。 数据库服务器使用聚类标准来按照排序顺序自动将事务表中的行存储在事实表中的某些用户启动的数据库操作上。