Method and mechanism for retrieving values from a database
    1.
    发明授权
    Method and mechanism for retrieving values from a database 失效
    从数据库检索值的方法和机制

    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

    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。