公开(公告)号：US20070061288A1

公开(公告)日：2007-03-15

申请号：US11222886

申请日：2005-09-09

申请人： You-Chin Fuh ,  Fen-Ling Lin ,  Andrei Lurie ,  Terence Purcell ,  Yoichi Tsuji ,  Li Xia

发明人： You-Chin Fuh ,  Fen-Ling Lin ,  Andrei Lurie ,  Terence Purcell ,  Yoichi Tsuji ,  Li Xia

IPC分类号： G06F17/30

CPC分类号： G06F17/30466 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99934

摘要： Provided are a techniques for processing a query including semi-joins. At execution time, a next semi-join is selected from the semi-joins for execution in a current round of semi-join executions. A reporting threshold is determined that indicates a number of record-identifiers to be retrieved for the determined semi-join. The selected semi-join is executed until the determined number of record identifiers are retrieved.

摘要翻译： 提供了用于处理包括半连接的查询的技术。 在执行时，从半连接中选择下一个半连接，以便在当前一轮的半连接执行中执行。 确定报告阈值，其指示要为所确定的半连接检索的记录标识符的数量。 执行所选择的半连接，直到检索到确定的记录标识数量。

公开(公告)号：US06980981B2

公开(公告)日：2005-12-27

申请号：US10143410

申请日：2002-05-10

申请人： Thomas Abel Beavin ,  You-Chin Fuh ,  Joseph F. Sinnott, Jr.

发明人： Thomas Abel Beavin ,  You-Chin Fuh ,  Joseph F. Sinnott, Jr.

IPC分类号： G06F17/30

CPC分类号： G06F17/30466 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99937 ,  Y10S707/99938 ,  Y10S707/99942 ,  Y10S707/99943

摘要： Provided are a method, system, and program for selecting a join order for tables subject to a join operation. An estimation is made of a join cost to perform joins on permutations of at least two of the tables, wherein each join permutation indicates an order of joining the tables. A determination is made as to whether sufficient computational resources are available to perform a join cost analysis of further join permutations of the tables. If sufficient computational resources are not available, then a determination is made of a restricted subset of remaining join permutations of at least two of the tables for which join costs have not been estimated that is less than all the remaining join permutations. The join costs of permutations of tables in the restricted subset is estimated and the estimated join costs are used to select one join permutation of all the tables having a lowest estimated join cost.

摘要翻译： 提供了一种用于选择连接操作的表的连接顺序的方法，系统和程序。 估计在至少两个表的排列上执行连接的连接成本，其中每个连接置换指示连接表的顺序。 确定足够的计算资源是否可用于执行表的进一步连接排列的连接成本分析。 如果没有足够的计算资源，则确定尚未估计连接成本小于所有其余连接置换的表中至少两个的剩余连接置换的受限子集。 估计受限子集中表的排列的连接成本，并且使用估计的连接成本来选择具有最低估计连接成本的所有表的一个连接排列。

公开(公告)号：US20050234900A1

公开(公告)日：2005-10-20

申请号：US10824856

申请日：2004-04-14

申请人： Patrick Bossman ,  You-Chin Fuh ,  Shuanglin Guo ,  Chan-Hua Liu ,  Yoichi Tsuji

发明人： Patrick Bossman ,  You-Chin Fuh ,  Shuanglin Guo ,  Chan-Hua Liu ,  Yoichi Tsuji

IPC分类号： G06F17/30

CPC分类号： G06F17/30306 ,  Y10S707/99932 ,  Y10S707/99934

摘要： In various embodiments, a method, apparatus, and article of manufacture collect statistics in a database management system. A workload comprising a plurality of database queries is received. Query statistics for the database queries are identified. The query statistics for the database queries are consolidated to provide consolidated statistics. One or more statistics collection requests are generated based on the consolidated statistics.

摘要翻译： 在各种实施例中，方法，装置和制品在数据库管理系统中收集统计数据。 接收包括多个数据库查询的工作负载。 识别数据库查询的查询统计信息。 合并数据库查询的查询统计信息以提供统一统计信息。 基于统一统计信息生成一个或多个统计信息收集请求。

公开(公告)号：US07895185B2

公开(公告)日：2011-02-22

申请号：US11536400

申请日：2006-09-28

申请人： Ying-Lin Chen ,  You-Chin Fuh ,  Fen-Ling Lin ,  Terence Patrick Purcell ,  Ying Zeng

发明人： Ying-Lin Chen ,  You-Chin Fuh ,  Fen-Ling Lin ,  Terence Patrick Purcell ,  Ying Zeng

IPC分类号： G06F17/30

CPC分类号： G06F17/30492 ,  G06F17/30321

摘要： A method, computer program product, and system for managing row identifier (RID) list processing on an index are provided. The method, computer program product, and system provide for accessing one or more key values in the index based on one or more keys specified in a query, retrieving a plurality of row identifiers corresponding to the one or more key values from the index, and predicting an actual number of row identifiers to be retrieved from the index based on the one or more key values accessed and the plurality of row identifiers retrieved.

摘要翻译： 提供了一种用于管理索引上的行标识符（RID）列表处理的方法，计算机程序产品和系统。 该方法，计算机程序产品和系统提供了基于查询中指定的一个或多个键访问索引中的一个或多个键值，从索引检索对应于一个或多个键值的多个行标识符，以及 基于所访问的一个或多个键值和检索的多个行标识符来预测要从索引检索的行标识符的实际数量。

公开(公告)号：US07814072B2

公开(公告)日：2010-10-12

申请号：US11028186

申请日：2004-12-30

申请人： Patrick Dooling Bossman ,  You-Chin Fuh ,  Shuanglin Guo ,  Chan-hua Liu ,  Yoichi Tsuji ,  Changjiu Xian

发明人： Patrick Dooling Bossman ,  You-Chin Fuh ,  Shuanglin Guo ,  Chan-hua Liu ,  Yoichi Tsuji ,  Changjiu Xian

IPC分类号： G06F17/00

CPC分类号： G06F17/30315

摘要： A method of, a computer program product for and a computer system for managing statistics in a database management system are provided. A value of a volatility of a statistic is determined. A value of a staleness of the statistic is determined using the value of the volatility. A statistics collection task is generated in response to, at least in part, the value of the staleness exceeding a value of a staleness threshold. The statistics collection task is executed to collect an additional value of the statistic. The additional value of the statistic is stored.

摘要翻译： 提供了一种用于管理数据库管理系统中的统计的计算机程序产品和计算机系统的方法。 确定统计量的波动率的值。 使用波动率的值确定统计量的平均值。 响应于至少部分地响应于超过平常阈值的陈旧值的值来生成统计收集任务。 执行统计信息收集任务以收集统计信息的附加值。 存储统计信息的附加值。

公开(公告)号：US20090012945A1

公开(公告)日：2009-01-08

申请号：US12212431

申请日：2008-09-17

申请人： Yao-Ching Chen ,  You-Chin Fuh ,  Allan B. Lebovitz ,  Li-Mey Lee ,  Fen-Ling Lin ,  Lee-Chin Hsu Liu ,  Yun Wang ,  Binghua Zhen

发明人： Yao-Ching Chen ,  You-Chin Fuh ,  Allan B. Lebovitz ,  Li-Mey Lee ,  Fen-Ling Lin ,  Lee-Chin Hsu Liu ,  Yun Wang ,  Binghua Zhen

IPC分类号： G06F17/30

CPC分类号： G06F17/30595 ,  Y10S707/99933 ,  Y10S707/99937

摘要： A system and computer readable medium for executing a query to access data stored in a database, wherein the query includes a plurality of DISTINCT keys, is disclosed. The system and computer readable medium includes a capture module for identifying each of the plurality of DISTINCT keys in the query and a sort module coupled to the capture module for determining if more than one sort is needed to execute the query, performing a first DISTINCT operation on a first DISTINCT key of the plurality of DISTINCT keys, storing data fetched from the first DISTINCT operation in a master workfile only if more than one sort process is needed to execute the query, and utilizing the master workfile to perform subsequent DISTINCT operations on the other of the plurality of DISTINCT keys.

摘要翻译： 一种用于执行查询以访问存储在数据库中的数据的系统和计算机可读介质，其中所述查询包括多个DISTINCT键。 所述系统和计算机可读介质包括用于识别所述查询中的所述多个DISTINCT密钥中的每一个的捕获模块和耦合到所述捕获模块的分类模块，用于确定是否需要多于一种排序来执行所述查询，执行第一DISTINCT操作 在多个DISTINCT密钥的第一DISTINCT密钥上，仅当需要多于一个排序处理来执行查询时，将从第一个DISTINCT操作获取的数据存储在主工作文件中，并且利用主工作文件执行后续的DISTINCT操作 多个DISTINCT键中的其他键。

公开(公告)号：US20080082489A1

公开(公告)日：2008-04-03

申请号：US11536400

申请日：2006-09-28

申请人： Ying-Lin CHEN ,  You-Chin Fuh ,  Fen-Ling Lin ,  Terence Patrick Purcell ,  Ying Zeng

发明人： Ying-Lin CHEN ,  You-Chin Fuh ,  Fen-Ling Lin ,  Terence Patrick Purcell ,  Ying Zeng

IPC分类号： G06F17/30

CPC分类号： G06F17/30492 ,  G06F17/30321

摘要： A method, computer program product, and system for managing row identifier (RID) list processing on an index are provided. The method, computer program product, and system provide for accessing one or more key values in the index based on one or more keys specified in a query, retrieving a plurality of row identifiers corresponding to the one or more key values from the index, and predicting an actual number of row identifiers to be retrieved from the index based on the one or more key values accessed and the plurality of row identifiers retrieved.

摘要翻译： 提供了一种用于管理索引上的行标识符（RID）列表处理的方法，计算机程序产品和系统。 该方法，计算机程序产品和系统提供了基于查询中指定的一个或多个键访问索引中的一个或多个键值，从索引检索对应于一个或多个键值的多个行标识符，以及 基于所访问的一个或多个键值和检索的多个行标识符来预测要从索引检索的行标识符的实际数量。

公开(公告)号：US20070011143A1

公开(公告)日：2007-01-11

申请号：US11176601

申请日：2005-07-06

申请人： You-Chin Fuh ,  Ping Wang ,  Li Xia ,  Binghua Zhen

发明人： You-Chin Fuh ,  Ping Wang ,  Li Xia ,  Binghua Zhen

IPC分类号： G06F17/30

CPC分类号： G06F17/30864 ,  G06F17/30657 ,  Y10S707/99933

摘要： Techniques are provided for processing a query using an index. It is determined whether a number of consecutive keys that evaluate to a false-positive when applying a screening predicate in the query exceeds a false-positive predefined value. One or more keys in the index are skipped in response to determining that the number of consecutive keys exceeds the false-positive predefined value.

摘要翻译： 提供了使用索引处理查询的技术。 确定在查询中应用筛选谓词时评估为假阳性的多个连续密钥是否超过假阳性预定义值。 响应于确定连续键的数量超过假阳性预定义值，跳过索引中的一个或多个键。

公开(公告)号：US07139749B2

公开(公告)日：2006-11-21

申请号：US10373237

申请日：2003-02-24

申请人： Patrick Dooling Bossman ,  You-Chin Fuh ,  Chan-Hua Liu ,  Ping Wang ,  Yun Wang ,  Jie Zhang

发明人： Patrick Dooling Bossman ,  You-Chin Fuh ,  Chan-Hua Liu ,  Ping Wang ,  Yun Wang ,  Jie Zhang

IPC分类号： G06F17/30

CPC分类号： G06F17/30306 ,  Y10S707/99931 ,  Y10S707/99933 ,  Y10S707/99935 ,  Y10S707/99943 ,  Y10S707/99945

摘要： Provided are a method, system, an program for tuning a database query. Provided are a base access plan to implement the database query and statistics including information on a layout of the database against which the query will be executed. The statistics are processed to determine performance problems with the base access plan as part of a first analysis of the base access plan and the determined performance problems are processed as part of a second analysis to provide an analysis of the determined performance problems and processing cost of the base access plan. Recommendations are generated to tune the base access plan to improve performance.

公开(公告)号：US20060212658A1

公开(公告)日：2006-09-21

申请号：US11083289

申请日：2005-03-18

申请人： Namik Hrle ,  You-Chin Fuh ,  Yoichi Tsuji ,  Li Xia

发明人： Namik Hrle ,  You-Chin Fuh ,  Yoichi Tsuji ,  Li Xia

IPC分类号： G06F12/00

CPC分类号： G06F12/0862

摘要： Embodiments of the present invention provide a “look-ahead” form prefetch. Look-ahead prefetch may utilize a look-ahead queue to prefetch multiple pages asynchronously. The look-ahead queue may hold a plurality of search keys that are related to a transaction. When accessing a table, an index manager may retrieve the table's index and scan the index based on the search keys from the look-ahead queue to find the RIDs in the table that match the search keys. The index manager may then accumulate these RIDs into a prefetch list. A prefetch manager may read the prefetch list, determine locations for the pages of the table that contain the records identified by the RIDs, and dispatch prefetch tasks to the appropriate storage device for these pages.

摘要翻译： 本发明的实施例提供了一种“先行”形式预取。 先行预取可以利用预先队列来异步预取多个页面。 先行队列可以保存与事务相关的多个搜索关键字。 当访问表时，索引管理器可以检索表的索引并基于来自先行队列的搜索键来扫描索引，以找到表中与搜索关键字匹配的RID。 索引管理器然后可以将这些RID累加到预取列表中。 预取管理器可以读取预取列表，确定包含由RID标识的记录的表的页面的位置，以及将这些页面的预取任务分派到适当的存储设备。