-
1.发明申请TECHNIQUES FOR MORE EFFICIENT GENERATION OF XML EVENTS FROM XML DATA SOURCES 有权从XML数据源更有效地生成XML事件的技术公开(公告)号：US20090125693A1
公开(公告)日：2009-05-14
申请号：US11938020
申请日：2007-11-09
IPC分类号： G06F13/00
CPC分类号： G06F17/272 , G06F17/2247 , G06F17/30938
摘要： One may increase the efficiency of an XML event-generating process by reducing the number of requests to allocate or deallocate system memory. Such reduction may occur as the result of pre-allocating a memory chunk of sufficient size to contain all of the memory buffers required by a particular event-generating process. Instead of allocating new memory chunks for new memory buffers, an application may store any required buffers within the pre-allocated memory chunk. A sufficient memory size may be estimated by performing the event-generating process on a training set of XML documents. Also, an application may re-use buffers during the process or between different iterations of the process, thus avoiding the need to deallocate and reallocate memory that is essentially being used for the same purpose.
摘要翻译： 可以通过减少分配或释放系统内存的请求数来提高XML事件生成过程的效率。 这种减少可以作为预先分配足够大小的存储器块以包含特定事件生成过程所需的所有存储器缓冲器的结果而发生。 代替为新的内存缓冲区分配新的内存块，应用程序可以在预先分配的内存块内存储任何所需的缓冲区。 可以通过对XML文档的训练集执行事件生成过程来估计足够的存储器大小。 此外，应用程序可以在进程期间或在进程的不同迭代之间重新使用缓冲区，从而避免需要释放并重新分配基本上被用于相同目的的存储器。
-
公开(公告)号：US20090125495A1
公开(公告)日：2009-05-14
申请号：US11938017
申请日：2007-11-09
IPC分类号： G06F17/30
CPC分类号： G06F17/30938 , G06F17/2247 , G06F17/2258
摘要： A database system may perform a streaming evaluation of an XPath expression by utilizing an XPath evaluation component in tandem with an XML event-streaming component. For a more optimal filtered streaming evaluation, the XML event-streaming component may provide an interface whereby the evaluation component sends certain criteria to the event-streaming component when requesting an XML event. The criteria may be based on a next unmatched step in the XPath expression. In response to the request for an XML event, the event-streaming component may only return events that match the criteria. The evaluation component may be, for example, a compiled state machine for the XPath expression. The criteria may be pre-compiled for each possible state in the state machine. The event-streaming component may also utilize the criteria along with schema information to skip parsing of certain segments of XML data.
摘要翻译： 数据库系统可以通过与XML事件流组件一起使用XPath评估组件来执行XPath表达式的流评估。 对于更优化的过滤流评估，XML事件流组件可以提供一个接口，当请求XML事件时，评估组件向事件流组件发送特定标准。 标准可能基于XPath表达式中的下一个不匹配的步骤。 响应对XML事件的请求，事件流组件可能只返回符合条件的事件。 评估组件可以是例如XPath表达式的编译状态机。 可以对状态机中的每个可能的状态预先准备标准。 事件流组件还可以利用标准以及模式信息来跳过某些XML数据段的解析。
-
3.发明授权Query optimization by specifying path-based predicate evaluation in a path-based query operator 有权通过在基于路径的查询运算符中指定基于路径的谓词评估来查询优化公开(公告)号：US08161035B2
公开(公告)日：2012-04-17
申请号：US12478147
申请日：2009-06-04
IPC分类号： G06F17/30
CPC分类号： G06F17/30938 , G06F17/30463
摘要： The approaches described herein provide an efficient way for a database server to process certain kinds of queries over XML data stored in an object-relational database that require the evaluation of a predicate expression with one or more path-based operands. A predicate expression part of a XQuery or SQL WHERE clause that returns a boolean value. A database server first determines whether the query qualifies for this particular kind of optimization, then rewrites the query using an enhanced query operator syntax for specifying the predicate expression to be evaluated. The enhanced query operator subsumes the work of a second path-based query operator, resulting in the suppression of the WHERE EXISTS subquery. The rewritten query operator is used to generate a query execution plan that provides for several query execution optimizations.
摘要翻译： 本文描述的方法为数据库服务器处理某些类型的查询提供了一种有效的方法，该XML数据存储在需要使用一个或多个基于路径的操作数的谓词表达式的对象关系数据库中。 XQuery或SQL WHERE子句的谓词表达式部分，返回一个布尔值。 数据库服务器首先确定查询是否符合此特定类型的优化，然后使用增强型查询运算符语法重写查询，以指定要评估的谓词表达式。 增强型查询操作符包含第二个基于路径的查询运算符的工作，从而抑制了WHERE EXISTS子查询。 重写的查询运算符用于生成提供多个查询执行优化的查询执行计划。
-
4.发明授权Techniques for more efficient generation of XML events from XML data sources 有权从XML数据源更有效地生成XML事件的技术公开(公告)号：US08543898B2
公开(公告)日：2013-09-24
申请号：US11938020
申请日：2007-11-09
IPC分类号： G06F17/00
CPC分类号： G06F17/272 , G06F17/2247 , G06F17/30938
摘要： One may increase the efficiency of an XML event-generating process by reducing the number of requests to allocate or deallocate system memory. Such reduction may occur as the result of pre-allocating a memory chunk of sufficient size to contain all of the memory buffers required by a particular event-generating process. Instead of allocating new memory chunks for new memory buffers, an application may store any required buffers within the pre-allocated memory chunk. A sufficient memory size may be estimated by performing the event-generating process on a training set of XML documents. Also, an application may re-use buffers during the process or between different iterations of the process, thus avoiding the need to deallocate and reallocate memory that is essentially being used for the same purpose.
摘要翻译： 可以通过减少分配或释放系统内存的请求数来提高XML事件生成过程的效率。 这种减少可以作为预先分配足够大小的存储器块以包含特定事件生成过程所需的所有存储器缓冲器的结果而发生。 代替为新的内存缓冲区分配新的内存块，应用程序可以在预先分配的内存块内存储任何所需的缓冲区。 可以通过对XML文档的训练集执行事件生成过程来估计足够的存储器大小。 此外，应用程序可能会在进程期间或在进程的不同迭代之间重新使用缓冲区，从而避免需要重新分配和重新分配基本上用于相同目的的内存。
-
公开(公告)号：US08429196B2
公开(公告)日：2013-04-23
申请号：US12134196
申请日：2008-06-06
CPC分类号： G06F17/30923
摘要： Techniques are provided for efficiently extracting scalar values from binary-encoded XML data. Node information is stored in association with binary-encoded XML data to indicate whether one or more nodes of an XML document are simple or complex. A node is simple if the node has no child elements and no attributes. The node information of a particular node is used to determine whether a particular node, identified in a query, is simple or complex. If the particular node is simple, then the scalar value of the particular node is identified without performing any operations other than possibly converting the scalar value to a non-binary-encoded format or converting the scalar value to a value of a different data type.
摘要翻译： 提供了从二进制编码的XML数据高效地提取标量值的技术。 节点信息与二进制编码的XML数据相关联地存储以指示XML文档的一个或多个节点是简单还是复杂的。 如果节点没有子元素而没有属性，则节点很简单。 特定节点的节点信息用于确定在查询中标识的特定节点是简单还是复杂。 如果特定节点是简单的，则特定节点的标量值被识别，而不执行除可能将标量值转换为非二进制编码格式之外的任何操作，或者将标量值转换为不同数据类型的值。
-
公开(公告)号：US08200679B2
公开(公告)日：2012-06-12
申请号：US12328642
申请日：2008-12-04
IPC分类号： G06F17/00
CPC分类号： G06F17/30935
摘要： Techniques are provided for estimating the cardinality of a virtual result table that is produced by executing path-based table functions within a query, such as the XMLTABLE function. Some path-based table functions apply a path expression to input from a base table of XML documents to select rows to produce the result table. Path statistics are collected for the path expressions for the base table. The path statistics are used to estimate the cardinalities of the result table. The estimated cardinality of the result table is useful for estimating costs of query execution plans that are generated for the query.
摘要翻译： 提供了用于估计通过在查询中执行基于路径的表函数（例如XMLTABLE函数）产生的虚拟结果表的基数的技术。 一些基于路径的表函数将路径表达式应用于从XML文档的基表中输入，以选择行以生成结果表。 针对基表的路径表达式收集路径统计信息。 路径统计信息用于估计结果表的基数。 结果表的估计基数对于为查询生成的查询执行计划的估计成本很有用。
-
公开(公告)号：US08024325B2
公开(公告)日：2011-09-20
申请号：US12145659
申请日：2008-06-25
申请人： Ning Zhang , Sam Idicula , Nipun Agarwal
发明人： Ning Zhang , Sam Idicula , Nipun Agarwal
CPC分类号： G06F17/30463 , G06F17/30929
摘要： Techniques for estimating the cost of processing a database statement that includes one or more path expressions are provided. One aspect of cost is I/O cost, or the cost of reading data from persistent storage into memory according to a particular streaming operator. Binary-encoded XML data is stored in association with a synopsis that summarizes the binary-encoded XML data. The synopsis includes skip length information for one or more elements and indicates, for each such element, how large (e.g., in bytes) the element is in storage. The skip length information of a particular element thus indicates how much data may be skipped during I/O if the particular element does not match the path expression that is input to the streaming operator. The skip length information of one or more elements is used to estimate the cost of processing the database statement.
摘要翻译： 提供了用于估计处理包含一个或多个路径表达式的数据库语句的成本的技术。 成本的一个方面是I / O成本，或者根据特定的流媒体运营商从永久存储器读取数据到存储器的成本。 二进制编码的XML数据与总结二进制编码的XML数据的概要相关联地存储。 概要包括一个或多个元素的跳过长度信息，并且针对每个这样的元素指示该元素在存储中的大小（例如，以字节为单位）。 因此，特定元素的跳过长度信息因此表示如果特定元素与输入到流媒体操作者的路径表达式不匹配，则可以在I / O期间跳过多少数据。 一个或多个元素的跳过长度信息用于估计处理数据库语句的成本。
-
公开(公告)号：US08250062B2
公开(公告)日：2012-08-21
申请号：US11938017
申请日：2007-11-09
CPC分类号： G06F17/30938 , G06F17/2247 , G06F17/2258
摘要： A database system may perform a streaming evaluation of an XPath expression by utilizing an XPath evaluation component in tandem with an XML event-streaming component. For a more optimal filtered streaming evaluation, the XML event-streaming component may provide an interface whereby the evaluation component sends certain criteria to the event-streaming component when requesting an XML event. The criteria may be based on a next unmatched step in the XPath expression. In response to the request for an XML event, the event-streaming component may only return events that match the criteria. The evaluation component may be, for example, a compiled state machine for the XPath expression. The criteria may be pre-compiled for each possible state in the state machine. The event-streaming component may also utilize the criteria along with schema information to skip parsing of certain segments of XML data.
摘要翻译： 数据库系统可以通过与XML事件流组件一起使用XPath评估组件来执行XPath表达式的流评估。 对于更优化的过滤流评估，XML事件流组件可以提供一个接口，当请求XML事件时，评估组件向事件流组件发送特定标准。 标准可能基于XPath表达式中的下一个不匹配的步骤。 响应对XML事件的请求，事件流组件可能只返回符合条件的事件。 评估组件可以是例如XPath表达式的编译状态机。 可以对状态机中的每个可能的状态预先准备标准。 事件流组件还可以利用标准以及模式信息来跳过某些XML数据段的解析。
-
9.发明申请Query Optimization by Specifying Path-Based Predicate Evaluation in a Path-Based Query Operator 有权通过在基于路径的查询运算符中指定基于路径的谓词评估来进行查询优化公开(公告)号：US20100312756A1
公开(公告)日：2010-12-09
申请号：US12478147
申请日：2009-06-04
IPC分类号： G06F7/00
CPC分类号： G06F17/30938 , G06F17/30463
摘要： The approaches described herein provide an efficient way for a database server to process certain kinds of queries over XML data stored in an object-relational database that require the evaluation of a predicate expression with one or more path-based operands. A predicate expression part of a XQuery or SQL WHERE clause that returns a boolean value. A database server first determines whether the query qualifies for this particular kind of optimization, then rewrites the query using an enhanced query operator syntax for specifying the predicate expression to be evaluated. The enhanced query operator subsumes the work of a second path-based query operator, resulting in the suppression of the WHERE EXISTS subquery. The rewritten query operator is used to generate a query execution plan that provides for several query execution optimizations.
摘要翻译： 本文描述的方法为数据库服务器处理某些类型的查询提供了一种有效的方法，该XML数据存储在需要使用一个或多个基于路径的操作数的谓词表达式的对象关系数据库中。 XQuery或SQL WHERE子句的谓词表达式部分，返回一个布尔值。 数据库服务器首先确定查询是否符合此特定类型的优化，然后使用增强型查询运算符语法重写查询，以指定要评估的谓词表达式。 增强型查询操作符包含第二个基于路径的查询运算符的工作，从而抑制了WHERE EXISTS子查询。 重写的查询运算符用于生成提供多个查询执行优化的查询执行计划。
-
公开(公告)号：US20100145957A1
公开(公告)日：2010-06-10
申请号：US12328642
申请日：2008-12-04
CPC分类号： G06F17/30935
摘要： Techniques are provided for estimating the cardinality of a virtual result table that is produced by executing path-based table functions within a query, such as the XMLTABLE function. Some path-based table functions apply a path expression to input from a base table of XML documents to select rows to produce the result table. Path statistics are collected for the path expressions for the base table. The path statistics are used to estimate the cardinalities of the result table. The estimated cardinality of the result table is useful for estimating costs of query execution plans that are generated for the query.
摘要翻译： 提供了用于估计通过在查询中执行基于路径的表函数（例如XMLTABLE函数）产生的虚拟结果表的基数的技术。 一些基于路径的表函数将路径表达式应用于从XML文档的基表中输入，以选择行以生成结果表。 针对基表的路径表达式收集路径统计信息。 路径统计信息用于估计结果表的基数。 结果表的估计基数对于为查询生成的查询执行计划的估计成本很有用。
-
-
-
-
-
-
-
-
-
搜索结果
119 条记录 (耗时 0.023 秒)
