公开(公告)号：US20080183644A1

公开(公告)日：2008-07-31

申请号：US11669782

申请日：2007-01-31

申请人： Nicolas Bruno ,  Surajit Chaudhuri

发明人： Nicolas Bruno ,  Surajit Chaudhuri

IPC分类号： G06F15/18 ,  G06F12/00 ,  G06F13/00

CPC分类号： G06F17/30306

摘要： A lightweight physical design alerter can analyze a workload and determine whether a comprehensive tuning session would result in a configuration improvement over the current configuration. The alerter provides a low-overhead procedure that can run during normal operation of a database management system and produce a notification if a current configuration is less than optimal. The alerter can report lower and upper bounds on the improvements that could be obtained if a comprehensive tuning tool is launched. A lower bound can be justified by generating feasible configurations. The disclosed embodiments can be extended to query updates, materialized views, and other physical design features (e.g., partitioning).

摘要翻译： 轻量级物理设计报警器可以分析工作负载并确定综合调优会话是否会导致配置改进超过当前配置。 报警器提供了一个低开销的过程，可以在数据库管理系统的正常操作期间运行，并在当前配置不太适合的情况下产生通知。 报警器可以报告如果启动综合调整工具可以获得的改进的上下限。 可以通过生成可行的配置来证明下限。 所公开的实施例可以扩展到查询更新，物化视图和其他物理设计特征（例如，分区）。

公开(公告)号：US07363289B2

公开(公告)日：2008-04-22

申请号：US11177598

申请日：2005-07-07

申请人： Surajit Chaudhuri ,  Nicolas Bruno

发明人： Surajit Chaudhuri ,  Nicolas Bruno

IPC分类号： G06F17/30

CPC分类号： G06F17/30463 ,  G06F17/30536 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99942 ,  Y10S707/99943 ,  Y10S707/99944 ,  Y10S707/99945

摘要： A method for evaluating a user query on a relational database having records stored therein, a workload made up of a set of queries that have been executed on the database, and a query optimizer that generates a query execution plan for the user query. Each query plan includes a plurality of intermediate query plan components that verify a subset of records from the database meeting query criteria. The method accesses the query plan and a set of stored intermediate statistics for records verified by query components, such as histograms that summarize the cardinality of the records that verify the query component. The method forms a transformed query plan based on the selected intermediate statistics (possibly by rewriting the query plan) and estimates the cardinality of the transformed query plan to arrive at a more accurate cardinality estimate for the query. If additional intermediate statistics are necessary, a pool of intermediate statistics may be generated based on the queries in the workload by evaluating the benefit of a given statistic over the workload and adding intermediate statistics to the pool that provide relatively great benefit.

摘要翻译： 一种用于评估具有存储在其中的记录的关系数据库的用户查询的方法，由在数据库上执行的一组查询组成的工作负载以及生成用户查询的查询执行计划的查询优化器。 每个查询计划包括多个中间查询计划组件，其从数据库会议查询条件验证记录的子集。 该方法访问查询计划和一组存储的中间统计信息，用于查询组件验证的记录，例如总结验证查询组件的记录的基数的直方图。 该方法基于所选择的中间统计（可能通过重写查询计划）形成转换的查询计划，并且估计转换后的查询计划的基数以得到查询的更准确的基数估计。 如果需要额外的中间统计数据，则可以根据工作负载中的查询生成中间统计数据池，方法是评估给定统计量对工作负载的好处，并将中间统计信息添加到提供相对较大收益的池中。

公开(公告)号：US07249141B2

公开(公告)日：2007-07-24

申请号：US10426235

申请日：2003-04-30

申请人： Sanjay Agrawal ,  Surajit Chaudhuri ,  Abhinandan Das ,  Vivek Narasayya

发明人： Sanjay Agrawal ,  Surajit Chaudhuri ,  Abhinandan Das ,  Vivek Narasayya

IPC分类号： G06F17/30 ,  G06F7/00

CPC分类号： G06F17/30595 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99943

摘要： Layout in a database system is performed using workload information. Execution information for a workload is obtained. Cumulative access and co-access information for database objects is then assembled. A cost model is developed for quantitatively capturing the value of different layouts, and a search is performed for a recommended database layout. In one embodiment, a greedy search is performed which initially attempts provide a layout that minimizes co-location of objects on storage objects, and then attempts to improve that layout via a greedy search.

摘要翻译： 使用工作负载信息执行数据库系统中的布局。 获取工作负载的执行信息。 然后组合数据库对象的累积访问和共存信息。 开发了一种成本模型，用于定量捕获不同布局的值，并为推荐的数据库布局执行搜索。 在一个实施例中，执行贪婪搜索，其最初尝试提供使存储对象上的对象的共同定位最小化的布局，然后尝试通过贪婪搜索来改进该布局。

公开(公告)号：US20060085463A1

公开(公告)日：2006-04-20

申请号：US11296034

申请日：2005-12-07

申请人： Surajit Chaudhuri ,  Vivek Narasayya ,  Rajeev Motwani ,  Mayur Datar

发明人： Surajit Chaudhuri ,  Vivek Narasayya ,  Rajeev Motwani ,  Mayur Datar

IPC分类号： G06F7/00

CPC分类号： G06F17/30536 ,  G06F17/30489 ,  Y10S707/99931 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99942

摘要： An outlier index for a database and a given workload is generated by identifying sub-relations of tuples in the database induced by selection and group by conditions in queries in the workload. A variance is then generated for values in each sub-relation. Sub-relations having higher variances are selected, and outliers from such sub-relations having higher variances are generated.

公开(公告)号：US20060036600A1

公开(公告)日：2006-02-16

申请号：US11246355

申请日：2005-10-07

申请人： Surajit Chaudhuri ,  Vivek Narasayya ,  Rajeev Motwani ,  Mayur Datar

发明人： Surajit Chaudhuri ,  Vivek Narasayya ,  Rajeev Motwani ,  Mayur Datar

IPC分类号： G06F7/00

CPC分类号： G06F17/30489 ,  G06F17/30536 ,  G06F2216/03 ,  Y10S707/957 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99935 ,  Y10S707/99942 ,  Y10S707/99943

摘要： Aggregation queries are performed by first identifying outlier values, aggregating the outlier values, and sampling the remaining data after pruning the outlier values. The sampled data is extrapolated and added to the aggregated outlier values to provide an estimate for each aggregation query. Outlier values are identified by selecting values outside of a selected sliding window of data having the lowest variance. An index is created for the outlier values. The outlier data is removed from the window of data, and separately aggregated. The remaining data without the outliers is then sampled to provide a statistically relevant sample that is then aggregated and extrapolated to provide an estimate for the remaining data. This sampled estimate is combined with the outlier aggregate to form an estimate for the entire set of data.

公开(公告)号：US20050222965A1

公开(公告)日：2005-10-06

申请号：US10813963

申请日：2004-03-31

申请人： Surajit Chaudhuri ,  Vivek Narasayya ,  Ravishankar Ramamurthy

发明人： Surajit Chaudhuri ,  Vivek Narasayya ,  Ravishankar Ramamurthy

IPC分类号： G06F7/00 ,  G06F17/30

CPC分类号： G06F17/30522 ,  G06F17/30306 ,  Y10S707/99932 ,  Y10S707/99945 ,  Y10S707/99948

摘要： A query progress indicator that provides an indication to a user of the progress of a query being executed on a database. The indication of the progress of the query allows the user to decide whether the query should be allowed to complete or should be aborted. One method that may be used to estimate the progress of a query that is being executed on a database defines a model of work performed during execution of a query. The total amount of work that will be performed during execution of the query is estimated according to the model. The amount of work performed at a given point during execution of the query is estimated according to the model. The progress of the query is estimated using the estimated amount of work at the given point in time and the estimated total amount of work. This estimated progress of query execution may be provided to the user.

摘要翻译： 查询进度指示符，向用户提供在数据库上执行的查询的进度的指示。 查询进度的指示允许用户决定是否允许查询完成或应该被中止。 可用于估计在数据库上执行的查询的进度的一种方法定义了在查询执行过程中执行的工作模型。 根据模型估计执行查询期间执行的总工作量。 在执行查询期间在给定点执行的工作量根据模型进行估计。 查询的进度使用在给定时间点的估计工作量和估计的总工作量来估计。 可以向用户提供该估计的查询执行进度。

公开(公告)号：US20050033759A1

公开(公告)日：2005-02-10

申请号：US10935803

申请日：2004-09-08

申请人： Surajit Chaudhuri ,  Vivek Narasayya ,  Gantam Das

发明人： Surajit Chaudhuri ,  Vivek Narasayya ,  Gantam Das

IPC分类号： G06F17/30 ,  G06F17/00

CPC分类号： G06F17/30536 ,  G06F17/30489 ,  Y10S707/99933 ,  Y10S707/99934 ,  Y10S707/99936 ,  Y10S707/99937 ,  Y10S707/99943 ,  Y10S707/99945

摘要： A method for estimating the result of a query on a database having data records arranged in tables. The database has an expected workload that includes a set of queries that can be executed on the database. An expected workload is derived comprising a set of queries that can be executed on the database. A sample is constructed by selecting data records for inclusion in the sample in a manner that minimizes an estimation error when the data records are acted upon by a query in the expected workload to provide an expected workload to provide an expected result. The query accesses the sample and is executed on the sample, returning an estimated query result. The expected workload can be constructed by specifying a degree of overlap between records selected by queries in the given workload and records selected by queries in the expected workload.

摘要翻译： 一种用于估计具有以表格排列的数据记录的数据库的查询结果的方法。 数据库具有预期的工作负载，其中包括可在数据库上执行的一组查询。 导出预期的工作负载，包括可在数据库上执行的一组查询。 通过在以下方式选择数据记录来构建样本，以便在预期工作负载中通过查询对数据记录进行操作以最小化估计误差的方式，以提供预期的工作负载以提供预期结果的方式来选择包含在样本中的数据记录。 查询访问样本并在样本上执行，返回估计的查询结果。 可以通过指定给定工作负载中的查询选择的记录与预期工作负载中的查询所选择的记录之间的重叠程度来构建预期的工作负载。

公开(公告)号：US06542886B1

公开(公告)日：2003-04-01

申请号：US09268275

申请日：1999-03-15

申请人： Surajit Chaudhuri ,  Rajeev Motwani ,  Vivek Narasayya

发明人： Surajit Chaudhuri ,  Rajeev Motwani ,  Vivek Narasayya

IPC分类号： G06F1730

CPC分类号： G06F17/3061 ,  G06F17/30498 ,  G06F17/30536 ,  G06F2216/03 ,  Y10S707/99932 ,  Y10S707/99937

摘要： A database server supports weighted and unweighted sampling of records or tuples in accordance with desired sampling semantics such as with replacement (WR), without replacement (WoR), or independent coin flips (CF) semantics, for example. The database server may perform such sampling sequentially not only to sample non-materialized records such as those produced as a stream by a pipeline in a query tree for example, but also to sample records, whether materialized or not, in a single pass. The database server also supports sampling over a join of two relations of records or tuples without requiring the computation of the full join and without requiring the materialization of both relations and/or indexes on the join attribute values of both relations.

摘要翻译： 数据库服务器根据期望的抽样语义（例如替换（WR），无替换（WoR）或独立硬币翻转（CF））语义支持对记录或元组进行加权和未加权采样。 数据库服务器可以顺序地执行这样的采样，以便例如在查询树中通过流水线生成的诸如作为流生成的非物化记录，而且在单次通过中对采样记录（无论是否具体化）进行采样。 数据库服务器还支持对两个记录或元组关系的连接进行抽样，而不需要计算完整连接，而不需要在关系的连接属性值上实现关系和/或索引。

公开(公告)号：US06278989B1

公开(公告)日：2001-08-21

申请号：US09139835

申请日：1998-08-25

申请人： Surajit Chaudhuri ,  Rajeev Motwani ,  Vivek Narasayya

发明人： Surajit Chaudhuri ,  Rajeev Motwani ,  Vivek Narasayya

IPC分类号： G06F1730

CPC分类号： G06F17/30463 ,  G06F17/30536 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99942

摘要： Using adaptive random sampling with cross-validation helps determine when enough data of a database has been sampled to construct histograms on one or more columns of one or more tables of the database within a desired or predetermined degree of accuracy. An adaptive random sampling histogram construction tool constructs an approximate equi-height k-histogram using an initial sample of data values from the database and iteratively updates the histogram using an additional sample of data values from the database until the histogram is within the desired degree of accuracy. The accuracy of the histogram is cross-validated against the additional sample at each iteration, and the additional sample is used to update the histogram to help improve its accuracy. The accuracy of the histogram may be measured by an error in distribution of the additional sample over the histogram as compared to a threshold error using a suitable error metric. By attempting to sample only the number of data values necessary to construct the histogram within the desired degree of accuracy, the adaptive random sampling histogram construction tool attempts to avoid any cost increases in time and memory from sampling too many data values.

摘要翻译： 使用具有交叉验证的自适应随机抽样有助于确定在数据库的足够数据被采样以在期望的或预定的准确度内在数据库的一个或多个表的一个或多个列上构造直方图。 自适应随机抽样直方图构造工具使用来自数据库的数据值的初始样本构建近似等高k直方图，并使用来自数据库的附加数据值样本迭代地更新直方图，直到直方图在所需的程度 准确性。 在每次迭代时，直方图的精度与附加样本进行交叉验证，并且附加样本用于更新直方图以帮助提高其准确性。 与使用合适的误差度量的阈值误差相比，可以通过直方图上的附加样本的分布误差来测量直方图的精度。 通过尝试仅在所需精度范围内仅采样构建直方图所需的数据值的数量，自适应随机抽样直方图构造工具尝试避免在采样太多数据值时的时间和内存中的任何成本增加。

公开(公告)号：US5926813A

公开(公告)日：1999-07-20

申请号：US980829

申请日：1997-12-01

申请人： Surajit Chaudhuri ,  Vivek Narasayya

发明人： Surajit Chaudhuri ,  Vivek Narasayya

IPC分类号： G06F17/30

CPC分类号： G06F17/30312 ,  Y10S707/99931 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99935 ,  Y10S707/99942 ,  Y10S707/99953

摘要： An index selection tool helps reduce costs in time and memory in selecting an index configuration or set of indexes for use by a database server in accessing a database in accordance with a workload of queries. The index selection tool attempts to reduce the number of indexes to be considered, the number of index configurations to be enumerated, and the number of invocations of a query optimizer in selecting an index configuration for the workload.