Fatigue sensitivity determination procedure
    1.
    发明授权
    Fatigue sensitivity determination procedure 失效
    疲劳敏感度测定程序

    公开(公告)号:US06704664B2

    公开(公告)日:2004-03-09

    申请号:US10025530

    申请日:2001-12-18

    IPC分类号: G01B344

    摘要: A method for determining the sensitivity of the fatigue life of a structural component with respect to specific design parameters includes obtaining the stress profile for a structural component under random process establishing a relationship between the stress profile and the fatigue life of the structural component, developing the sensitivity of the fatigue life with respect to design parameters, optimizing the design of the structural component based upon the design parameters to which the fatigue life is most sensitive.

    摘要翻译: 用于确定结构部件相对于具体设计参数的疲劳寿命的灵敏度的方法包括在随机过程下获得结构部件的应力分布,建立应力分布与结构部件的疲劳寿命之间的关系, 疲劳寿命对设计参数的敏感性,根据疲劳寿命最为敏感的设计参数优化结构件的设计。

    Join factorization of union/union all queries
    2.
    发明授权
    Join factorization of union/union all queries 有权
    加入联盟/联盟所有查询的因式分解

    公开(公告)号:US07644062B2

    公开(公告)日:2010-01-05

    申请号:US11716010

    申请日:2007-03-08

    IPC分类号: G06F7/00 G06F17/30

    摘要: Under a type of query transformation referred to herein as join factorization, the branches of an UNION/UNION ALL query that join a common table are combined to reduce accesses to the common table. The transformation can be expressed as (T1 join T2) union all (T1 join T3)=T1 join (T2 union all T3), where T1, T2 and T3 are three tables. A given query may be rewritten in many alternate ways using join factorization. Evaluating each alternative can be expensive. Therefore, the alternatives are generated and evaluated in a way that minimizes the cost of evaluating the alternatives.

    摘要翻译: 在这里称为连接因式分解的一种类型的查询变换中,加入公共表的UNION / UNION ALL查询的分支被组合以减少对公共表的访问。 转换可以表示为(T1连接T2)联合全部(T1连接T3)= T1连接(T2联合全T3),其中T1,T2和T3是三个表。 给定的查询可以使用连接因式分解以许多替代方式重写。 评估每个替代品可能是昂贵的。 因此,以最小化评估替代品的成本的方式生成和评估替代方案。

    Merging synopses to determine number of distinct values in large databases
    3.
    发明授权
    Merging synopses to determine number of distinct values in large databases 有权
    合并摘要以确定大型数据库中不同值的数量

    公开(公告)号:US07603339B2

    公开(公告)日:2009-10-13

    申请号:US11796110

    申请日:2007-04-25

    IPC分类号: G06F7/00 G06F17/30 G06F17/00

    摘要: A method and apparatus for merging synopses to determine a database statistic, e.g., a number of distinct values (NDV), is disclosed. The merging can be used to determine an initial database statistic or to perform incremental statistics maintenance. For example, each synopsis can pertain to a different partition, such that merging the synopses generates a global statistic. When performing incremental maintenance, only those synopses whose partitions have changed need to be updated. Each synopsis contains domain values that summarize the statistic. However, the synopses may initially contain domain values that are not compatible with each other. Prior to merging the synopses the domain values in each synopsis is made compatible with the domain values in the other synopses. The adjustment is made such that each synopsis represents the same range of domain values, in one embodiment. After “compatible synopses” are formed, the synopses are merged by taking the union of the compatible synopses.

    摘要翻译: 公开了用于合并概要以确定数据库统计量的方法和装置,例如多个不同值(NDV)。 合并可用于确定初始数据库统计信息或执行增量统计维护。 例如,每个概要可以涉及不同的分区,以便合并概要会生成全局统计量。 执行增量维护时,只需要更新其分区已更改的概要文件。 每个概要包含总结统计量的域值。 但是,这些概要可能最初包含彼此不兼容的域值。 在合并概要之前,每个概要中的域值与其他概要中的域值兼容。 在一个实施例中进行调整,使得每个概要表示相同范围的域值。 在形成“兼容简介”之后,通过兼容兼容简报的合并来合并概要。

    SQL execution plan baselines
    4.
    发明授权
    SQL execution plan baselines 有权
    SQL执行计划基线

    公开(公告)号:US09189522B2

    公开(公告)日:2015-11-17

    申请号:US12188678

    申请日:2008-08-08

    IPC分类号: G06F7/00 G06F17/00 G06F17/30

    CPC分类号: G06F17/30469 G06F17/30463

    摘要: Approaches, techniques, and mechanisms are disclosed for maintaining a set of baseline query plans for a database command. Except in rare circumstances, a database server may only execute a command according to a baseline plan, even if the database server predicts that a different plan has a lower cost. The set of baseline plans are plans that, for one reason or another, have been determined to provide acceptable actual performance in at least one execution context. When the database server receives a request to execute a particular command, the database server, if possible, always executes the command according to the lowest predicted cost baseline plan. The database server may evolve the plan baseline to include additional plans by generating and testing new plans in response to new requests to execute the database command, or as part of a query optimization or tuning process.

    摘要翻译: 披露了用于维护数据库命令的一组基线查询计划的方法,技术和机制。 除极少数情况下,数据库服务器只能根据基准线执行命令,即使数据库服务器预测不同的计划成本较低。 一组基准计划是由于某种原因决定在至少一个执行环境中提供可接受的实际绩效的计划。 当数据库服务器接收到执行特定命令的请求时,如果可能,数据库服务器总是根据最低预测成本基线计划执行该命令。 数据库服务器可以通过生成和测试新计划以响应执行数据库命令的新请求,或作为查询优化或调整过程的一部分,来演进计划基准以包括额外的计划。

    Approximating a database statistic
    5.
    发明申请
    Approximating a database statistic 有权
    近似数据库统计

    公开(公告)号:US20080120274A1

    公开(公告)日:2008-05-22

    申请号:US11796102

    申请日:2007-04-25

    IPC分类号: G06F7/00

    摘要: A method and apparatus for approximating a database statistic, such as the number of distinct values (NDV) is provided. To approximate the NDV for a portion of a table, a synopsis of distinct values is constructed. Each value in the portion is mapped to a domain of values. The mapping function is implemented with a uniform hash function, in one embodiment. If the resultant domain value does not exist in the synopsis, the domain value is added to the synopsis. If the synopsis reaches its capacity, a portion of the domain values are discarded from the synopsis. The statistic is approximated based on the number (N) of domain values in the synopsis and the portion of the domain that is represented in the synopsis relative to the size of the domain.

    摘要翻译: 提供了用于近似数据库统计量的方法和装置,例如不同值(NDV)的数量。 为了近似表的一部分的NDV,构建了不同值的概要。 该部分中的每个值都映射到值的域。 在一个实施例中,映射功能是用均匀散列函数实现的。 如果在概要中不存在结果域值,则将域值添加到概要中。 如果概要达到其容量,则域值的一部分将从摘要中被丢弃。 统计量基于概要中的域值的数量(N)和在概要中相对于域的大小表示的域的部分近似。

    Efficient search space analysis for join factorization
    6.
    发明申请
    Efficient search space analysis for join factorization 有权
    用于连接分解的高效搜索空间分析

    公开(公告)号:US20070219977A1

    公开(公告)日:2007-09-20

    申请号:US11716107

    申请日:2007-03-08

    IPC分类号: G06F17/30

    摘要: Under a type of query transformation referred to herein as join factorization, the branches of an UNION/UNION ALL query that join a common table are combined to reduce accesses to the common table. The transformation can be expressed as (T1 join T2) union all (T1 join T3)=T1 join (T2 union all T3), where T1, T2 and T3 are three tables. A given query may be rewritten in many alternate ways using join factorization. Evaluating each alternative can be expensive. Therefore, the alternatives are generated and evaluated in a way that minimizes the cost of evaluating the alternatives.

    摘要翻译: 在这里称为连接因式分解的一种类型的查询变换中,加入公共表的UNION / UNION ALL查询的分支被组合以减少对公共表的访问。 转换可以表示为(T 1连接T 2)联合全部(T 1连接T 3)= T 1连接(T 2并联全部T 3),其中T 1,T 2和T 3是三个表。 给定的查询可以使用连接因式分解以许多替代方式重写。 评估每个替代品可能是昂贵的。 因此,以最小化评估替代品的成本的方式生成和评估替代方案。

    Maintaining and utilizing SQL execution plan histories
    9.
    发明授权
    Maintaining and utilizing SQL execution plan histories 有权
    维护和利用SQL执行计划历史

    公开(公告)号:US08335767B2

    公开(公告)日:2012-12-18

    申请号:US12188673

    申请日:2008-08-08

    IPC分类号: G06F7/00 G06F17/00 G06F17/30

    CPC分类号: G06F17/30469 G06F17/30463

    摘要: Approaches, techniques, and mechanisms are disclosed for maintaining a history of query plans executed for a database command, along with information related to each query plan. A database server receives a request to execute a particular command. The database server determines a plan for executing the particular command. The database server adds first information to a plan history associated with the particular command. The plan history comprises information related to a plurality of plans that have been generated for the particular command. The first information may include, for example, properties of the plan (including an outline of the plan) as well as statistics collected during execution of the plan. The database server may implement techniques for periodically refreshing information in a plan history. The database server may also implement techniques for purging old or less important plans.

    摘要翻译: 公开了用于维护针对数据库命令执行的查询计划的历史以及与每个查询计划相关的信息的方法,技术和机制。 数据库服务器接收执行特定命令的请求。 数据库服务器确定执行特定命令的计划。 数据库服务器将第一个信息添加到与特定命令相关联的计划历史记录中。 计划历史包括与为特定命令生成的多个计划相关的信息。 第一个信息可以包括例如计划的属性(包括计划的纲要)以及执行计划期间收集的统计数据。 数据库服务器可以实现用于在计划历史中周期性地刷新信息的技术。 数据库服务器还可以实现用于清除旧的或不太重要的计划的技术。

    Approximating a database statistic
    10.
    发明授权
    Approximating a database statistic 有权
    近似数据库统计

    公开(公告)号:US07636731B2

    公开(公告)日:2009-12-22

    申请号:US11796102

    申请日:2007-04-25

    IPC分类号: G06F7/00 G06F17/30 G06F17/00

    摘要: A method and apparatus for approximating a database statistic, such as the number of distinct values (NDV) is provided. To approximate the NDV for a portion of a table, a synopsis of distinct values is constructed. Each value in the portion is mapped to a domain of values. The mapping function is implemented with a uniform hash function, in one embodiment. If the resultant domain value does not exist in the synopsis, the domain value is added to the synopsis. If the synopsis reaches its capacity, a portion of the domain values are discarded from the synopsis. The statistic is approximated based on the number (N) of domain values in the synopsis and the portion of the domain that is represented in the synopsis relative to the size of the domain.

    摘要翻译: 提供了用于近似数据库统计量的方法和装置,例如不同值(NDV)的数量。 为了近似表的一部分的NDV,构建了不同值的概要。 该部分中的每个值都映射到值的域。 在一个实施例中,映射功能是用均匀散列函数实现的。 如果在概要中不存在结果域值,则将域值添加到概要中。 如果概要达到其容量,则域值的一部分将从摘要中被丢弃。 统计量基于概要中的域值的数量(N)和在概要中相对于域的大小表示的域的部分近似。