公开(公告)号：US06330552B1

公开(公告)日：2001-12-11

申请号：US09162638

申请日：1998-09-28

申请人： Christopher M. Farrar ,  Harry A. Leslie ,  Pedro Celis ,  Diana L. Shak ,  Jay H. Vaishnav ,  Michael J. Skarpelos

发明人： Christopher M. Farrar ,  Harry A. Leslie ,  Pedro Celis ,  Diana L. Shak ,  Jay H. Vaishnav ,  Michael J. Skarpelos

IPC分类号： G06F1760

CPC分类号： G06Q10/04 ,  G06Q30/0283 ,  Y10S707/99931 ,  Y10S707/99932

摘要： A method and apparatus is disclosed for accurately estimating the cost of a database query, including the total computer resources used and estimated elapsed time for the production of a first row and last row of an operator involved in the query and/or the total resources used and elapsed time for returning the overall response to a database query. The method and apparatus accurately accounts for resources used and elapsed time associated with blocking operators, such as sorts and hash joins, which cannot produce a first row until they have completed their operations.

摘要翻译： 公开了一种用于精确估计数据库查询的成本的方法和装置，包括所使用的总计算机资源和用于生成涉及查询的运营商的第一行和最后一行的估计经过时间和/或所使用的总资源 以及将整体响应返回到数据库查询的时间。 该方法和装置准确地说明了与阻塞运算符（例如排序和散列连接）相关联的资源所用的资源和经过的时间，在完成其操作之前不能产生第一行。

公开(公告)号：US06263345B1

公开(公告)日：2001-07-17

申请号：US09162245

申请日：1998-09-28

申请人： Christopher M. Farrar ,  Harry A. Leslie ,  Pedro Celis ,  Diana L. Shak

发明人： Christopher M. Farrar ,  Harry A. Leslie ,  Pedro Celis ,  Diana L. Shak

IPC分类号： G06F1730

CPC分类号： G06F17/30454 ,  G06F17/30463 ,  G06F17/30536 ,  Y10S707/954 ,  Y10S707/966 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99945

摘要： The invention provides a mechanism for using statistics, in connection with various database query cost modeling techniques, to more accurately estimate the number of rows and UECs that will be produced by relational operators and predicates in database systems. The ability to accurately estimate the number of rows and UECs returned by a relational operator and/or a predicate is fundamental to computing the cost of a query execution plan. This, in turn, drives the optimizer's ability to select the query plan best suited for the desired performance goal. According to the present invention, histogram statistics are synthesized bottom up from the leaf nodes to the root node of a query tree. Given input statistics in the form of histograms for each operand of a relational operator or predicate, the present inventive method and apparatus merge the input statistics in a way that it simulates the effects of the run time operator on the actual data, so as to produce a predicted row count and UEC for each histogram interval representative of the data that actually will be produced by each such operator or predicate in the query tree. A database query optimizer may use these statistics to select and implement an optimal query plan.

摘要翻译： 本发明提供了一种使用统计学的机制，结合各种数据库查询成本建模技术来更精确地估计将由数据库系统中的关系运算符和谓词产生的行数和UEC。 精确估计关系运算符和/或谓词返回的行数和UEC的能力是计算查询执行计划成本的基础。 这反过来又推动了优化器选择最适合于所需性能目标的查询计划的能力。 根据本发明，从查询树的叶节点到根节点从下向上合成直方图统计量。 给定关系运算符或谓词的每个操作数的直方图形式的输入统计量，本发明的方法和装置以输入统计的方式合并输入统计量，以便模拟运行时间算子对实际数据的影响，从而产生 每个直方图间隔的预测行数和UEC代表实际将由查询树中的每个这样的运算符或谓词产生的数据。 数据库查询优化器可以使用这些统计信息来选择和实现最优查询计划。

公开(公告)号：US20080270368A1

公开(公告)日：2008-10-30

申请号：US11740457

申请日：2007-04-26

申请人： Curt L. Cotner ,  Christopher M. Farrar ,  Robert T. Miller ,  Maryela F. Weihrauch

发明人： Curt L. Cotner ,  Christopher M. Farrar ,  Robert T. Miller ,  Maryela F. Weihrauch

IPC分类号： G06F7/00

CPC分类号： G06F17/30463 ,  G06F17/30306

摘要： An apparatus, system, and method are disclosed for efficiently supporting generic SQL data manipulation statements. The method includes determining whether an SQL statement includes extended indicator parameters such as DEFAULT and UNASSIGNED indicators. The method further includes delaying an authorization check for an operation for an SQL statement using extended indicators, and bypassing an SQL exception where an otherwise unauthorized operation involves an UNASSIGNED variable. The method further includes bypassing a database operation such as a referential integrity check where a data change would induce the database operation, but the data change involves an UNASSIGNED variable. The method further includes modifying the SQL statement when the SQL statement involves an UNASSIGNED variable in a predicate clause, allowing the SQL statement to properly execute.

摘要翻译： 公开了用于有效支持通用SQL数据操作语句的装置，系统和方法。 该方法包括确定SQL语句是否包含扩展指示符参数，如DEFAULT和UNASSIGNED指示符。 该方法还包括使用扩展指示器延迟对SQL语句的操作的授权检查，以及绕过除非未经授权的操作涉及UNASSIGNED变量的SQL异常。 该方法还包括绕过诸如引用完整性检查的数据库操作，其中数据改变将引起数据库操作，但数据更改涉及UNASSIGNED变量。 该方法还包括在SQL语句涉及到谓词子句中的UNASSIGNED变量时修改SQL语句，从而允许SQL语句正确执行。

公开(公告)号：US07716213B2

公开(公告)日：2010-05-11

申请号：US11740457

申请日：2007-04-26

申请人： Curt L. Cotner ,  Christopher M. Farrar ,  Robert T. Miller ,  Maryela E. Weihrauch

发明人： Curt L. Cotner ,  Christopher M. Farrar ,  Robert T. Miller ,  Maryela E. Weihrauch

IPC分类号： G06F7/00

CPC分类号： G06F17/30463 ,  G06F17/30306

摘要： An apparatus, system, and method are disclosed for efficiently supporting generic SQL data manipulation statements. The method includes determining whether an SQL statement includes extended indicator parameters such as DEFAULT and UNASSIGNED indicators. The method further includes delaying an authorization check for an operation for an SQL statement using extended indicators, and bypassing an SQL exception where an otherwise unauthorized operation involves an UNASSIGNED variable. The method further includes bypassing a database operation such as a referential integrity check where a data change would induce the database operation, but the data change involves an UNASSIGNED variable. The method further includes modifying the SQL statement when the SQL statement involves an UNASSIGNED variable in a predicate clause, allowing the SQL statement to properly execute.

摘要翻译： 公开了用于有效支持通用SQL数据操作语句的装置，系统和方法。 该方法包括确定SQL语句是否包含扩展指示符参数，如DEFAULT和UNASSIGNED指示符。 该方法还包括使用扩展指示器延迟对SQL语句的操作的授权检查，以及绕过除非未经授权的操作涉及UNASSIGNED变量的SQL异常。 该方法还包括绕过诸如引用完整性检查的数据库操作，其中数据改变将引起数据库操作，但数据更改涉及UNASSIGNED变量。 该方法还包括在SQL语句涉及到谓词子句中的UNASSIGNED变量时修改SQL语句，从而允许SQL语句正确执行。