Method and apparatus for dynamically associating different query execution strategies with selective portions of a database table
    1.
    发明申请
    Method and apparatus for dynamically associating different query execution strategies with selective portions of a database table 失效
    用于将不同查询执行策略与数据库表的选择性部分动态关联的方法和装置

    公开(公告)号:US20070016558A1

    公开(公告)日:2007-01-18

    申请号:US11181713

    申请日:2005-07-14

    IPC分类号: G06F17/30

    CPC分类号: G06F17/3053 G06F17/30545

    摘要: A query facility for database queries dynamically determines whether selective portions of a database table are likely to benefit from separate query execution strategies, and constructs an appropriate separate execution strategies accordingly. Preferably, the database contains at least one relatively large table comprising multiple partitions, each sharing the definitional structure of the table and containing a different respective discrete subset of the table records. The query facility compares metadata for different partitions to determine whether sufficiently large differences exist among the partitions, and in appropriate cases selects one or more partitions for separate execution strategies. Preferably, partitions are ranked for separate evaluation using a weighting formula which takes into account: (a) the number of indexes for the partition, (b) recency of change activity, and (c) the size of the partition.

    摘要翻译: 用于数据库查询的查询工具动态地确定数据库表的选择性部分是否可能受益于单独的查询执行策略,并相应地构建适当的单独的执行策略。 优选地,数据库包含至少一个包括多个分区的相对较大的表,每个分区共享表的定义结构,并且包含表记录的不同相应离散子集。 查询设施比较不同分区的元数据,以确定分区之间是否存在足够大的差异,并且在适当的情况下选择一个或多个分区用于单独的执行策略。 优选地,使用考虑到的加权公式对分区进行分级评估:(a)分区的索引的数量,(b)更改活动的新近度,以及(c)分区的大小。

    Method and apparatus for associating logical conditions with the re-use of a database query execution strategy
    2.
    发明申请
    Method and apparatus for associating logical conditions with the re-use of a database query execution strategy 有权
    将逻辑条件与数据库查询执行策略的重用相关联的方法和装置

    公开(公告)号:US20060224561A1

    公开(公告)日:2006-10-05

    申请号:US11094655

    申请日:2005-03-30

    IPC分类号: G06F17/30

    摘要: A query facility for database queries saves and re-uses query execution strategies, and automatically determines whether a strategy can be re-used when an imported variable changes. The query facility automatically saves one or more logical conditions associated with the one or more imported variables in the query. When the query is reused, the logical conditions are evaluated using the imported variable values, and the previously saved execution strategy is used only if the condition or conditions are met. Preferably, the logical conditions express a range of imported variable values which are included in a database subset data structure used by the saved query execution strategy, such as a materialized query table or partitioned table. Logical conditions are preferably generated by negating the predicates from a logical expression defining the applicability of the execution strategy, inserting the negated predicates into the query, and performing a transitive closure.

    摘要翻译: 数据库查询的查询功能可以保存并重新使用查询执行策略,并自动确定在导入的变量更改时是否可以重新使用策略。 查询设备自动保存与查询中的一个或多个导入的变量相关联的一个或多个逻辑条件。 当重新使用查询时,使用导入的变量值来评估逻辑条件,并且仅当满足条件或条件时才使用先前保存的执行策略。 优选地,逻辑条件表示包括在由保存的查询执行策略(例如物化查询表或分区表)使用的数据库子集数据结构中的导入变量值的范围。 逻辑条件优选地通过从定义执行策略的适用性,将否定的谓词插入到查询中并且执行传递闭包的逻辑表达式来取消谓词来产生。

    Look-ahead predicate generation for join costing and optimization
    3.
    发明申请
    Look-ahead predicate generation for join costing and optimization 审中-公开
    前瞻性谓词生成用于连接成本核算和优化

    公开(公告)号:US20050160102A1

    公开(公告)日:2005-07-21

    申请号:US10758485

    申请日:2004-01-15

    IPC分类号: G06F7/00 G06F17/30

    CPC分类号: G06F16/2456

    摘要: A relational database system analyzes each potential join in a query, to determine whether a relation involved in the join is subject to a selection criterion, and evaluate whether that selection criterion or the join per se effects a join reduction. The computational expense of generating a look-ahead predicate comprising the tuples of the second relation matching any applicable selection criterion, is compared to the computational savings that result from the join reduction. The most beneficial look-ahead predicate among all potential joins of relations in the query is identified through iterative analysis of all possible joins. Thereafter, membership in the look-ahead predicate is added as a selection criterion on the first relation, and further iterative analysis is performed of all possible joins of the remaining relations and the look-ahead predicate, to iteratively identify additional joins in the query that benefit from the formation of the look-ahead predicate, and potentially form further look-ahead predicates.

    摘要翻译: 关系数据库系统分析查询中的每个潜在连接,以确定连接中涉及的关系是否受制于选择标准,并评估该选择标准或连接本身是否影响连接缩减。 将包括与任何适用的选择标准相匹配的第二关系的元组的生成预先谓词的计算费用与由连接减少产生的计算节省进行比较。 通过对所有可能的连接进行迭代分析,可以确定查询中关系中所有潜在联系中最有利的预言谓词。 此后,将先行谓词的成员资格作为关于第一关系的选择标准被添加,并且对剩余关系和先行谓词的所有可能连接执行进一步的迭代分析,以迭代地识别查询中的附加联接 受益于先行谓词的形成,并可能形成进一步的预言谓词。

    Method and Apparatus for Autonomically Maintaining Latent Auxiliary Database Structures for Use in Executing Database Queries
    4.
    发明申请
    Method and Apparatus for Autonomically Maintaining Latent Auxiliary Database Structures for Use in Executing Database Queries 审中-公开
    用于自动维护潜在辅助数据库结构的方法和装置,用于执行数据库查询

    公开(公告)号:US20070250517A1

    公开(公告)日:2007-10-25

    申请号:US11379503

    申请日:2006-04-20

    IPC分类号: G06F7/00

    摘要: A latent auxiliary database structure constructed for executing a query is automatically saved for reuse in subsequent query execution instances. The latent auxiliary database structure is not maintained concurrently with changes to records in the database tables. If a query execution strategy is subsequently invoked which uses the latent auxiliary database structure, a determination is made dynamically whether to update the previously saved latent structure from database changes recorded in one or more change logs, or to rebuild the latent structure from scratch. Where the cost of updating from the change log is deemed less than the cost of a rebuild from scratch, the previously saved latent structure is updated from the log.

    摘要翻译: 构建用于执行查询的潜在辅助数据库结构将自动保存,以便在后续查询执行实例中重用。 潜在辅助数据库结构与数据库表中记录的更改不同时维护。 如果随后调用使用潜在辅助数据库结构的查询执行策略,则动态确定是否从先前保存的潜在结构更新记录在一个或多个更改日志中的数据库更改,或从头重新构建潜在结构。 在从更改日志更新成本被认为小于从头开始重建的成本的情况下,先前保存的潜在结构将从日志中更新。

    Apparatus and method for optimizing a query to a partitioned database table using a virtual maintained temporary index that spans multiple database partitions
    5.
    发明申请
    Apparatus and method for optimizing a query to a partitioned database table using a virtual maintained temporary index that spans multiple database partitions 审中-公开
    使用跨多个数据库分区的虚拟维护临时索引来优化对分区数据库表的查询的装置和方法

    公开(公告)号:US20070226176A1

    公开(公告)日:2007-09-27

    申请号:US11388004

    申请日:2006-03-23

    IPC分类号: G06F17/30

    CPC分类号: G06F16/2246

    摘要: A query optimizer optimizes a query to a partitioned database table by determining common characteristics of the partitions and generating a virtual maintained temporary index that spans multiple partitions. Using the virtual maintained temporary index allows the query optimizer to generate an access plan based on the virtual maintained temporary index, which relieves the optimizer from having to individually optimize access to each partition for partitions that share common characteristics.

    摘要翻译: 查询优化器通过确定分区的共同特征并生成跨多个分区的虚拟维护临时索引来优化对分区数据库表的查询。 使用虚拟维护的临时索引允许查询优化器基于虚拟维护的临时索引生成访问计划,这减轻了优化器必须单独优化对共享共同特征的分区的每个分区的访问。

    Continual generation of index advice
    6.
    发明申请
    Continual generation of index advice 审中-公开
    连续生成索引建议

    公开(公告)号:US20070073761A1

    公开(公告)日:2007-03-29

    申请号:US11239617

    申请日:2005-09-29

    IPC分类号: G06F7/00

    CPC分类号: G06F16/217 G06F16/22

    摘要: Continual generation of index advice that includes generating an index advice for an index of a table in a computer database and recording values of statistical attributes of the index advice accumulated across repeated generations of the index advice. The generating and recording typically are carried out continually without user intervention. Embodiments include recording values of attributes of the index advice that specify an index. Typical embodiments also include, continually and without user intervention, recording values of attributes of the index advice that characterize usefulness of an index and recording values of attributes of the index advice that characterize cost of creating an index.

    摘要翻译: 持续生成索引建议,包括为计算机数据库中的表的索引生成索引建议,并记录索引建议的重复次数累积的索引建议的统计属性的值。 生成和记录通常在没有用户干预的情况下持续进行。 实施例包括记录指定索引的索引建议的属性的值。 典型实施例还包括持续地且没有用户干预的记录索引建议的属性的值,其表征索引的有用性,并记录表征创建索引的成本的索引建议的属性的值。

    Displaying explain data for a SQL query of a database
    7.
    发明申请
    Displaying explain data for a SQL query of a database 审中-公开
    显示数据库的SQL查询的说明数据

    公开(公告)号:US20060095406A1

    公开(公告)日:2006-05-04

    申请号:US10977801

    申请日:2004-10-29

    IPC分类号: G06F17/30

    CPC分类号: G06F16/217 G06F16/24547

    摘要: Enabling a user to obtain and view graphic explain data with no need to activate a monitor and no need to wait for a job to complete before the explain data for a query may be viewed. Displaying explain data for an SQL query of a database that include executing an SQL query and displaying explain data for the SQL query while executing the SQL query. Displaying explain data includes identifying an access plan associated with the SQL query and generating explain data in dependence upon the access plan. Identifying an access plan may be carried out by retrieving an access plan identification from a cursor of a job control block and retrieving an access plan from an access plan cache in dependence upon the access plan identification.

    摘要翻译: 允许用户获取和查看图形说明数据,无需激活监视器,无需等待作业完成,才能查看查询的说明数据。 显示数据库的SQL查询的解释数据,其中包括执行SQL查询并在执行SQL查询时显示SQL查询的说明数据。 显示说明数据包括识别与SQL查询相关联的访问计划,并根据访问计划生成说明数据。 识别访问计划可以通过从作业控制块的光标检索访问计划标识并且根据访问计划标识从访问计划高速缓存检索访问计划来执行访问计划。

    REMOVING NODES FROM A QUERY TREE BASED ON A RESULT SET
    8.
    发明申请
    REMOVING NODES FROM A QUERY TREE BASED ON A RESULT SET 审中-公开
    根据结果​​集从查询树中删除编号

    公开(公告)号:US20070239673A1

    公开(公告)日:2007-10-11

    申请号:US11278714

    申请日:2006-04-05

    IPC分类号: G06F17/30

    CPC分类号: G06F16/24542

    摘要: In an embodiment, a query tree is created that represents a query expression, where the query tree includes a union of nodes. Each of the nodes represents a respective partition of a table, and the query expression specifies a key value and the table. A determination is made whether a result set exists that includes the key value, where the result set was previously retrieved from the table. If the determination is true, a decision is made based on the result set whether the key value is stored in the respective partition represented by each of the nodes. The nodes for which the key value is not stored in the respective partition are removed from the query tree to create an optimization tree, and the optimization tree is used to retrieve data from the table. In this way, nodes that are not necessary to be searched may be removed from query trees, in order to increase the performance of the query.

    摘要翻译: 在一个实施例中,创建表示查询表达式的查询树,其中查询树包括节点的并集。 每个节点表示表的相应分区,查询表达式指定键值和表。 确定是否存在包含键值的结果集,其中先前从表中检索结果集。 如果确定为真,则基于结果集确定密钥值是否存储在由每个节点表示的相应分区中。 键值不存储在相应分区中的节点从查询树中删除以创建优化树,并且优化树用于从表中检索数据。 以这种方式,可以从查询树中删除不需要搜索的节点,以便增加查询的性能。

    Method and apparatus for projecting the effect of maintaining an auxiliary database structure for use in executing database queries
    9.
    发明申请
    Method and apparatus for projecting the effect of maintaining an auxiliary database structure for use in executing database queries 有权
    用于预测维护辅助数据库结构以用于执行数据库查询的效果的方法和装置

    公开(公告)号:US20070192372A1

    公开(公告)日:2007-08-16

    申请号:US11353515

    申请日:2006-02-14

    IPC分类号: G06F17/30

    CPC分类号: G06F17/30289 G06F17/30386

    摘要: A database management system maintains a record of queries which can be executed against the database. For a given auxiliary database structure, an advisory function automatically reviews the query record and identifies those queries which might execute with greater efficiency using the auxiliary database structure, presenting analytical information to the user. Preferably, the auxiliary database structure is an index, and the information is used for determining whether to include the index in the database definition. Preferably, a query optimizer records potentially useful indexes when considering multiple alternative database optimizations, and this information is later retrieved to identify queries which would benefit from an index.

    摘要翻译: 数据库管理系统维护可以针对数据库执行的查询记录。 对于给定的辅助数据库结构,咨询功能自动审查查询记录,并使用辅助数据库结构识别可能以更高效率执行的查询,向用户呈现分析信息。 优选地,辅助数据库结构是索引,并且该信息用于确定是否将数据包括在数据库定义中。 优选地,当考虑多个备选数据库优化时,查询优化器记录潜在有用的索引,并且稍后检索该信息以识别将从索引中受益的查询。

    Method and apparatus for eliminating partitions of a database table from a join query using implicit limitations on a partition key value
    10.
    发明申请
    Method and apparatus for eliminating partitions of a database table from a join query using implicit limitations on a partition key value 审中-公开
    使用对分区键值的隐含限制,从连接查询中消除数据库表的分区的方法和装置

    公开(公告)号:US20070027860A1

    公开(公告)日:2007-02-01

    申请号:US11191470

    申请日:2005-07-28

    IPC分类号: G06F17/30

    CPC分类号: G06F16/24544 G06F16/24524

    摘要: A database facility supports database join queries in a database environment having at least one database table divided into multiple partitions based on a partition key value. The facility determines whether the values in a table joined to the partitioned table place an implicit limitation on the partition key, and eliminates from query evaluation any partitions which do not satisfy the implicit limitation. Preferably, the database uses a star schema organization, in which implicit limitations in a relatively small dimension table are used to eliminate partitions in a relatively large fact table.

    摘要翻译: 数据库设施支持数据库环境中的数据库连接查询,其中至少有一个基于分区键值划分成多个分区的数据库表。 该设施确定连接到分区表的表中的值是否对分区关键字产生隐式限制,并且从查询评估中排除不满足隐式限制的任何分区。 优选地,数据库使用星型模式组织,其中使用相对较小维度表中的隐含限制来消除较大事实表中的分区。