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公开(公告)号：US08255387B2
公开(公告)日：2012-08-28
申请号：US12833670
申请日：2010-07-09
IPC分类号： G06F7/00
CPC分类号： G06F17/30321 , G06F17/30427
摘要： Technologies for forming logical indexes and utilizing such indexes so as to abstract many of the complexities resulting from referencing partitioned database tables. Included are technologies for making use of order-preserving properties of table metadata, for adding a partition equality predicate to an explicit predicate in merge-join processing on partitioned tables, and for selecting execution of a logical skip scan on a partitioned table when a query predicate does not reference a specific partition. Such technologies generally abstract from the query writer and processing systems explicit referencing of table partitions.
摘要翻译： 用于形成逻辑索引和利用这些索引的技术，以便抽象引用分区数据库表导致的许多复杂性。 包括使用表元数据的顺序保留属性的技术，用于在分区表中的合并连接处理中向显式谓词添加分区相等谓词，以及在查询时选择分区表上逻辑跳过扫描的执行 谓词不引用特定分区。 这些技术通常从查询写入程序和处理系统中抽象出来显式引用表分区。
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公开(公告)号：US07599953B2
公开(公告)日：2009-10-06
申请号：US10998761
申请日：2004-11-29
IPC分类号： G06F17/30
CPC分类号： G06F17/30501 , G06F17/3046 , G06F17/30466 , G06F17/30498 , Y10S707/99933 , Y10S707/99943
摘要： A method of satisfying a database query includes evaluating certain joins on a per-segment basis. An expression tree is produced for the query, and the expression tree is evaluated to identify joins whose operands are two instances of the same relation and whose join predicate conjunctively includes an equality comparison between two instances of the same column. When such a join is identified, it may be evaluated by segmenting the operand relation according to the columns that are compared for equality in the predicate. The join is then evaluated by performing the join operation separately on each segment. Segments may be spooled separately, thereby exploiting the efficiencies obtained by spooling even where the entire relation is too large to fit in the spool. Execution iterators are provided for spooling successive segments and for applying the join to the spooled segment.
摘要翻译： 满足数据库查询的方法包括基于每个段来评估某些联接。 为查询生成表达式树，并且对表达式树进行评估，以标识其操作数是相同关系的两个实例的连接，并且其连接谓词连接地包含同一列的两个实例之间的等效比较。 当识别出这样的连接时，可以通过根据在谓词中的相等性进行比较的列分割操作数关系来评估操作数关系。 然后通过在每个段上分别执行连接操作来评估连接。 分段可以单独地卷绕，从而利用即使在整个关系太大而不能装入卷轴的情况下通过卷绕获得的效率。 提供执行迭代器用于假脱机连续的段并将连接应用到假脱机段。
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公开(公告)号：US07509311B2
公开(公告)日：2009-03-24
申请号：US10652423
申请日：2003-08-29
IPC分类号： G06F17/30
CPC分类号： G06F17/30463 , G06F17/30536 , Y10S707/99933 , Y10S707/99934
摘要： A query optimizer produces a preferred execution plan by utilizing statistics on views. These provide the optimizer with statistical information beyond that available on tables, for example, with information on the result of scalar or relational expressions. Pre-derived accurate statistics are thus available which are used to improve the accuracy of estimation and thus increase the quality and reliability of the query processor. Transformations of expressions and sub-expressions of candidate plans produce equivalent sub-expressions. Where those sub-expressions include references to views, an estimation of the cardinality and other execution statistics for the sub-expression can be made using the view statistics. This can be used to estimate the cardinality for all equivalent sub-expressions, leading to higher accuracy for the estimate.
摘要翻译： 查询优化器通过利用视图统计信息生成首选执行计划。 这些为优化器提供超出表上可用的统计信息，例如，具有关于标量或关系表达式的结果的信息。 因此，可以使用预先导出的精确统计量来提高估计的准确性，从而提高查询处理器的质量和可靠性。 候选计划的表达式和子表达式的转换产生等效的子表达式。 在这些子表达式包括对视图的引用的情况下，可以使用视图统计信息来估计子表达式的基数和其他执行统计信息。 这可以用于估计所有等效子表达式的基数，导致估计的更高的准确性。
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公开(公告)号：US06510422B1
公开(公告)日：2003-01-21
申请号：US09671458
申请日：2000-09-27
IPC分类号： G06F1730
CPC分类号： G06F17/30457 , G06F17/30463 , Y10S707/99932 , Y10S707/99943
摘要： A query optimizer determines the applicability of materialized views to a query. View utilization alternatives are generated in the exploration stage of optimization, so that interaction with other transformations in complex queries is taken into account. A final decision on whether to use a materialized view is based on estimated cost. The optimizer generates a table of alternatives, which compactly encodes the various possibilities for each sub-expression of the query. Optimal-cost operator trees are extracted from this table. Materialized views are detected and substituted during exploration of the various possibilities and added to the table of alternatives. Materialized views and the alternatives are selected for use in a query execution plan based on cost. When two operator trees are not identical, a residual operator can be used if one operator tree subsumes the other operator tree. The residual expression can contain operators such as filters, group by and join.
摘要翻译： 查询优化器确定物化视图对查询的适用性。 在优化的探索阶段生成查看利用替代方案，以便考虑与复杂查询中的其他转换的交互。 是否使用物化视图的最终决定是基于估计成本。 优化器生成一个替代表，它可以紧密地编码查询的每个子表达式的各种可能性。 从该表中提取最优成本算子树。 在探索各种可能性期间检测和替换物化视图，并添加到替代表中。 物化视图和替代方案被选择用于基于成本的查询执行计划。 当两个运算符树不相同时，如果一个运算符树包含另一个运算符树，则可以使用剩余运算符。 残差表达式可以包含过滤器，分组和连接等运算符。
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5.发明授权System and method for incremental change synchronization between multiple copies of data 失效用于数据副本之间增量更改同步的系统和方法公开(公告)号：US06202085B1
公开(公告)日：2001-03-13
申请号：US08758739
申请日：1996-12-06
申请人： Max L. Benson , Dinarte Morais , Scott Norin , William P. Champion , Thomas F. Fakes , Milind M. Joshi
发明人： Max L. Benson , Dinarte Morais , Scott Norin , William P. Champion , Thomas F. Fakes , Milind M. Joshi
IPC分类号： G06F946
CPC分类号： G06F17/30008
摘要： A system and method for incremental change synchronization among multiple copies of data is disclosed. To achieve the synchronization a genera synchronization model is used. The synchronization model establishes a one-way data flow path to allow incremental changes to be transferred from a copy of data that incorporates the incremental changes to a copy of data that does not yet incorporate the incremental changes. To achieve this one-way data flow path, the synchronization model uses an agent, a data collector, and a data synchronizer. The data collector collects incremental changes transferred to it and applies the incremental changes to a copy of data. A data synchronizer transfers incremental changes to a data collector. An agent controls the synchronization process by making a connection between a data collector and a data synchronizer and then directing the data synchronizer to transfer data to the data collector. If bidirectional data flow is necessary to achieve synchronization between two copies of data, a one-way data flow path is established first in one direction and after all incremental changes have been passed in that direction, a data flow path is established in the opposite direction to pass incremental changes in the opposite direction.
摘要翻译： 公开了一种用于在多个数据副本之间进行增量改变同步的系统和方法。 为了实现同步，使用一个同步模型。 同步模型建立一个单向数据流路径，以允许将增量更改从包含增量更改的数据副本传输到尚未纳入增量更改的数据副本。 为了实现该单向数据流路径，同步模型使用代理，数据收集器和数据同步器。 数据收集器收集传递给它的增量更改，并将增量更改应用于数据副本。 数据同步器将增量更改传输到数据收集器。 代理通过在数据收集器和数据同步器之间进行连接来控制同步过程，然后指导数据同步器将数据传送到数据收集器。 如果需要双向数据流来实现两个数据副本之间的同步，则在一个方向上首先建立单向数据流路径，并且在所有增量更改已经沿该方向通过之后，沿相反方向建立数据流路径 在相反的方向传递增量变化。
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6.发明申请公开(公告)号：US20100274780A1
公开(公告)日：2010-10-28
申请号：US12833670
申请日：2010-07-09
IPC分类号： G06F17/30
CPC分类号： G06F17/30321 , G06F17/30427
摘要： Technologies for forming logical indexes and utilizing such indexes so as to abstract many of the complexities resulting from referencing partitioned database tables. Included are technologies for making use of order-preserving properties of table metadata, for adding a partition equality predicate to an explicit predicate in merge-join processing on partitioned tables, and for selecting execution of a logical skip scan on a partitioned table when a query predicate does not reference a specific partition. Such technologies generally abstract from the query writer and processing systems explicit referencing of table partitions.
摘要翻译： 用于形成逻辑索引和利用这些索引的技术，以便抽象引用分区数据库表导致的许多复杂性。 包括使用表元数据的顺序保留属性的技术，用于在分区表中的合并连接处理中向显式谓词添加分区相等谓词，以及在查询时选择分区表上逻辑跳过扫描的执行 谓词不引用特定分区。 这些技术通常从查询写入程序和处理系统中抽象出来显式引用表分区。
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公开(公告)号：US20090327214A1
公开(公告)日：2009-12-31
申请号：US12146423
申请日：2008-06-25
申请人： Andrew S. Richardson , Campbell Bryce Fraser , Cesar A. Galindo-Legaria , Torsten W. Grabs , Wei Yu , Milind M. Joshi
发明人： Andrew S. Richardson , Campbell Bryce Fraser , Cesar A. Galindo-Legaria , Torsten W. Grabs , Wei Yu , Milind M. Joshi
IPC分类号： G06F17/30
CPC分类号： G06F16/24545
摘要： Described is a query optimizer comprising a query tuner that performs actual execution of query fragments to obtain actual results during compilation time, and uses those actual results to select a query plan. The actual results may be combined with estimates for fragments that were not executed. The tree may be traversed in a top-down traversal, processing every node. Alternatively, the tree may be traversed in a bottom-up traversal, re-deriving data for higher nodes as each lower level is completed. A limit, such as a time limit or level limit, may be used to control how much time is taken to determine the execution plan.
摘要翻译： 描述了一种查询优化器，其包括执行查询片段的实际执行以在编译期间获得实际结果的查询调谐器，并且使用这些实际结果来选择查询计划。 实际结果可能与未执行的片段的估计相结合。 可以在上下遍历中遍历树，处理每个节点。 或者，可以在自下而上遍历中遍历树，在每个较低级完成时，重新导出较高节点的数据。 可以使用诸如时间限制或级别限制的限制来控制用于确定执行计划的时间。
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公开(公告)号：US07349897B2
公开(公告)日：2008-03-25
申请号：US11051447
申请日：2005-02-04
申请人： Conor J. Cunningham , Eric N. Hanson , Milind M. Joshi , Cesar A. Galindo-Legaria , Florian M. Waas
发明人： Conor J. Cunningham , Eric N. Hanson , Milind M. Joshi , Cesar A. Galindo-Legaria , Florian M. Waas
CPC分类号： G06F17/30451 , Y10S707/99932 , Y10S707/99933 , Y10S707/99934 , Y10S707/99935
摘要： Indexed views or materialized views are used as a secondary index on a base table with multi-valued attributes. This provides for using the index to search in the nested data. Moreover, indexing is provided on the result of an unnest operation. Indexing a view on the result of an unnesting operation provides the ability to index the contents of a nested collection. One such unnesting operation is “cross apply unnest”. This provides additional options for a query execution plan, leading to a more optimized query. A back-join is provided from the indexed view to the base table to allow fields from the base table that are not present in the indexed view to be included in a result of a query on the table which is processed using the indexed view as an access path. This provides a means of including columns in the query result that are not in the indexed view but are in the base table. The back-join is supported from a single-table indexed view to the base table via a unique clustering key which acts as a logical row locator. Thus, the system can back-join to the base table from an indexed view via the unique clustering key. These features allow the use of indexed views to index a table on the contents of multi-set or multi-valued attributes.
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9.发明授权System and method for cardinality estimation based on query execution feedback 有权基于查询执行反馈的基数估计系统和方法公开(公告)号：US07146363B2
公开(公告)日：2006-12-05
申请号：US10441812
申请日：2003-05-20
IPC分类号： G06F17/30
CPC分类号： G06F17/3046 , Y10S707/99932 , Y10S707/99936
摘要： During query execution, statistics associated with expressions are observed. Such observed statistics preferably include the cardinality of each expression. The observed statistics are submitted to an expression manager as feedback from the executed query. The statistics are preferably stored for use in estimating the cardinality of execution plans for future queries.
摘要翻译： 在查询执行期间，观察与表达式关联的统计信息。 这样观察到的统计数据优选地包括每个表达式的基数。 观察到的统计信息作为来自执行查询的反馈提交给表达式管理器。 统计数据优选地被存储以用于估计用于将来查询的执行计划的基数。
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10.发明授权Method and system for creating a database table index using multiple processors 失效使用多个处理器创建数据库表索引的方法和系统公开(公告)号：US06778977B1
公开(公告)日：2004-08-17
申请号：US09838691
申请日：2001-04-19
IPC分类号： G06F700
CPC分类号： G06F17/30327 , Y10S707/99932 , Y10S707/99942
摘要： A method and system for creating an index for a database table of records in a computer environment having a plurality of processing units wherein each processing unit has access to the database table. The method first determines partition delimiters wherein each partition delimiter separates the database table into non-overlapping partitions of records. Each of these partitions is dedicated to one processing unit for index creation. Next, each processing unit independently creates a sub-index, i.e., different processing units create at least two sub-indexes. Last, the method merges the sub-indexes together to create a final index related to the database table.
摘要翻译： 一种在具有多个处理单元的计算机环境中为记录的数据库表创建索引的方法和系统，其中每个处理单元都可以访问数据库表。 该方法首先确定分区分隔符，其中每个分区定界符将数据库表分成记录的非重叠分区。 这些分区中的每一个专用于一个用于索引创建的处理单元。 接下来，每个处理单元独立地创建子索引，即，不同的处理单元创建至少两个子索引。 最后，该方法将子索引合并在一起以创建与数据库表相关的最终索引。
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