公开(公告)号：US07644063B2

公开(公告)日：2010-01-05

申请号：US11840703

申请日：2007-08-17

申请人： Patrick D. Bossman ,  Frank D. Bower ,  John J. Campbell ,  You-Chin Fuh ,  Adarsh R. Pannu ,  Terrence P. Purcell

发明人： Patrick D. Bossman ,  Frank D. Bower ,  John J. Campbell ,  You-Chin Fuh ,  Adarsh R. Pannu ,  Terrence P. Purcell

IPC分类号： G06F17/30

CPC分类号： G06F17/30474

摘要： An apparatus, system, and method are disclosed for ensuring query execution plan stability in a database management system. The present invention binds a static database query to a new query execution plan (QEP) that produces the same result set as an original QEP bound to the static database query. Next, the present invention identifies one of the original QEP and the new QEP as a primary QEP and automatically collects execution statistics for the original QEP and the new QEP. Finally, the present invention automatically selects one of the original QEP and the new QEP as the primary QEP in response to completion of the automatic collection of execution statistics, the primary QEP selected such that the automatically selected QEP provides optimal execution performance based on performance criteria in comparison to the automatically unselected QEP, the primary QEP selected based on the execution statistics.

摘要翻译： 公开了一种用于确保数据库管理系统中的查询执行计划稳定性的装置，系统和方法。 本发明将静态数据库查询绑定到新的查询执行计划（QEP），该计划产生与绑定到静态数据库查询的原始QEP相同的结果集。 接下来，本发明将原始QEP和新QEP中的一个标识为主QEP，并自动收集原始QEP和新QEP的执行统计信息。 最后，本发明响应于完成执行统计的自动收集而自动选择原始QEP和新QEP中的一个作为主QEP，选择主QEP使得自动选择的QEP基于性能标准提供最佳执行性能 与自动未选择的QEP相比，基于执行统计信息选择主要QEP。