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公开(公告)号:US06374232B1
公开(公告)日:2002-04-16
申请号:US09103549
申请日:1998-06-24
IPC分类号: G06F1730
CPC分类号: G06F17/30327 , Y10S707/99932 , Y10S707/99933
摘要: An index is built upon on one more columns of a database table. In order to retrieve values from the database table, a block-order scan is performed on the index by sequentially reading one or more units of contiguous blocks of the index. For a B-tree index, branch nodes in the blocks are ignored, but column values from within leaf nodes are retrieved. The column whose values are read can be determined from processing a query that references the column. The index can be partitioned so that the block-order index can be performed on only some of the index. Moreover, the block-order index scan is suitable for a table organized as an index.
摘要翻译: 索引建立在数据库表的另外一列上。 为了从数据库表中检索值,通过依次读取索引的一个或多个连续块单元,对索引执行块顺序扫描。 对于B树索引,块中的分支节点被忽略,但是检索叶节点内的列值。 读取值的列可以通过处理引用该列的查询来确定。 可以对索引进行分区,以便仅对某些索引执行块顺序索引。 此外,块顺序索引扫描适用于组织为索引的表。