Providing a useable version of a data item
    1.
    发明授权
    Providing a useable version of a data item 有权
    提供数据项的可用版本

    公开(公告)号:US06957236B1

    公开(公告)日:2005-10-18

    申请号:US10263493

    申请日:2002-10-02

    IPC分类号: G06F12/00 G06F9/46 G06F17/30

    摘要: Techniques are provided for providing a data item to a transaction in a multi-versioning system in which the data item may exist on multiple versions of a data block, and were versioning is performed at the granularity of the data block. According to one aspect of the invention, the technique involves locating, within volatile memory, a first version of a data block that includes a first version of the data item. It is then determined whether the first version of the data item is useable by the transaction without respect to whether the first version of the data block is generally useable by the transaction. If the first version of the data item is usable by the transaction, then the data item is established as a candidate that can be provided to the transaction. Thus, the data item within a block may be considered a candidate to be provided to a transaction even when the version of the data block on which the data item resides would otherwise disqualify the data block from being seen by that transaction. If the first version of the data item is not usable by the transaction, then a version of the data item that is usable by the transaction is obtained from a second version of the data block that is different from the first version.

    摘要翻译: 提供了用于向多版本系统中的事务提供数据项的技术,其中数据项可以存在于数据块的多个版本上,并且以数据块的粒度执行版本控制。 根据本发明的一个方面,该技术涉及在易失性存储器内定位包括数据项的第一版本的数据块的第一版本。 然后确定该事务的第一版本的数据项是否可用,而不考虑该数据块的第一版本是否通常可被该事务使用。 如果数据项的第一个版本可以由事务使用,则数据项被建立为可以提供给事务的候选。 因此,即使当数据项所驻留的数据块的版本否则将使数据块被该事务看不到资格时,块内的数据项也可以被认为是被提供给事务的候选者。 如果数据项的第一版本不能被事务使用,则可以从与第一版本不同的数据块的第二版本获得事务可使用的数据项的版本。

    Adaptive filter index for determining queries affected by a DML operation
    2.
    发明授权
    Adaptive filter index for determining queries affected by a DML operation 有权
    用于确定受DML操作影响的查询的自适应过滤器索引

    公开(公告)号:US08185508B2

    公开(公告)日:2012-05-22

    申请号:US12326822

    申请日:2008-12-02

    IPC分类号: G06F17/30

    CPC分类号: G06F17/3051

    摘要: Techniques are disclosed for creating and using a filter index in order to identify registered queries whose result sets are likely to have been changed by changes made to tables. The filter index entries are based on filter conditions. The filter conditions are created based on predicates contained in the registered queries. The filter conditions may include exclusive predicates and join predicates. Join predicates that join a table T1 with a table T2 may be instantiated by replacing references to table T2 with values extracted from table T2. Various techniques are described for recognizing situations in which a query can be included in, or excluded from, the set of likely-changed queries, without fully evaluating the filter conditions that correspond to the queries.

    摘要翻译: 公开了用于创建和使用过滤器索引的技术,以便识别其结果集可能由于对表的改变而改变的注册查询。 过滤器索引条目基于过滤器条件。 过滤条件是根据注册查询中包含的谓词创建的。 过滤条件可能包括排除谓词和连接谓词。 可以通过用从表T2提取的值替换对表T2的引用来实例化加入具有表T2的表T1的连接谓词。 描述各种技术用于识别其中可以将查询包括在可能改变的查询集合中或从可能改变的查询集合中排除的情况,而不完全评估与查询相对应的过滤条件。

    Generating continuous query notifications
    3.
    发明授权
    Generating continuous query notifications 有权
    生成连续的查询通知

    公开(公告)号:US08037040B2

    公开(公告)日:2011-10-11

    申请号:US12189078

    申请日:2008-08-08

    IPC分类号: G06F17/30

    CPC分类号: G06F17/30516

    摘要: Techniques are described to allow a query to be registered as a persistent stored entity within the database, and to generate notifications as and when the query result changes continuously as long as the query continues to be registered with the database. According to one aspect, for a table referenced in a query, a filter condition is generated based, at least in part, on a predicate of the query. Then, the database server determines whether the filter condition is satisfied by either a before image of a row, or an after image of the row, that was modified by a transaction. If the filter condition is satisfied by either the before image or the after image, then the query is added to a first set of queries whose result sets may have been affected by the transaction. From among the first set of queries, a second set of queries that have result sets that were actually affected by the transaction is determined. Notifications are then sent based on the second set of queries.

    摘要翻译: 描述技术来允许将查询注册为数据库内的持久存储实体,并且只要查询继续向数据库注册,就可以随着查询结果不断更改而生成通知。 根据一个方面,对于在查询中引用的表,基于至少部分地基于查询的谓词生成过滤条件。 然后,数据库服务器通过由事务修改的行的先前图像或行的后续图像来确定滤波器条件是否满足。 如果过滤条件由前图像或后图像所满足,则将查询添加到其结果集可能受事务影响的第一组查询中。 从第一组查询中,确定具有实际受事务影响的结果集的第二组查询。 然后基于第二组查询发送通知。

    GENERATING CONTINUOUS QUERY NOTIFICATIONS
    4.
    发明申请
    GENERATING CONTINUOUS QUERY NOTIFICATIONS 有权
    生成连续查询通知

    公开(公告)号:US20100036831A1

    公开(公告)日:2010-02-11

    申请号:US12189078

    申请日:2008-08-08

    IPC分类号: G06F17/30

    CPC分类号: G06F17/30516

    摘要: Techniques are described to allow a query to be registered as a persistent stored entity within the database, and to generate notifications as and when the query result changes continuously as long as the query continues to be registered with the database. According to one aspect, for a table referenced in a query, a filter condition is generated based, at least in part, on a predicate of the query. Then, the database server determines whether the filter condition is satisfied by either a before image of a row, or an after image of the row, that was modified by a transaction. If the filter condition is satisfied by either the before image or the after image, then the query is added to a first set of queries whose result sets may have been affected by the transaction. From among the first set of queries, a second set of queries that have result sets that were actually affected by the transaction is determined. Notifications are then sent based on the second set of queries.

    摘要翻译: 描述技术来允许将查询注册为数据库内的持久存储实体,并且只要查询继续向数据库注册,就可以随着查询结果不断更改而生成通知。 根据一个方面,对于在查询中引用的表,基于至少部分地基于查询的谓词生成过滤条件。 然后,数据库服务器通过由事务修改的行的先前图像或行的后续图像来确定滤波器条件是否满足。 如果过滤条件由前图像或后图像所满足,则将查询添加到其结果集可能受事务影响的第一组查询中。 从第一组查询中,确定具有实际受事务影响的结果集的第二组查询。 然后基于第二组查询发送通知。

    ADAPTIVE FILTER INDEX FOR DETERMINING QUERIES AFFECTED BY A DML OPERATION
    5.
    发明申请
    ADAPTIVE FILTER INDEX FOR DETERMINING QUERIES AFFECTED BY A DML OPERATION 有权
    用于确定DML操作影响的自适应滤波器索引

    公开(公告)号:US20100036803A1

    公开(公告)日:2010-02-11

    申请号:US12326822

    申请日:2008-12-02

    IPC分类号: G06F7/06 G06F17/30

    CPC分类号: G06F17/3051

    摘要: Techniques are disclosed for creating and using a filter index in order to identify registered queries whose result sets are likely to have been changed by changes made to tables. The filter index entries are based on filter conditions. The filter conditions are created based on predicates contained in the registered queries. The filter conditions may include exclusive predicates and join predicates. Join predicates that join a table T1 with a table T2 may be instantiated by replacing references to table T2 with values extracted from table T2. Various techniques are described for recognizing situations in which a query can be included in, or excluded from, the set of likely-changed queries, without fully evaluating the filter conditions that correspond to the queries.

    摘要翻译: 公开了用于创建和使用过滤器索引的技术,以便识别其结果集可能由于对表的改变而改变的注册查询。 过滤器索引条目基于过滤器条件。 过滤条件是根据注册查询中包含的谓词创建的。 过滤条件可能包括排除谓词和连接谓词。 可以通过用从表T2提取的值替换对表T2的引用来实例化加入具有表T2的表T1的连接谓词。 描述各种技术用于识别其中可以将查询包括在可能改变的查询集合中或从可能改变的查询集合中排除的情况,而不完全评估与查询相对应的过滤条件。

    Methodology for hosting distributed objects at a predetermined node in a distributed system
    6.
    发明授权
    Methodology for hosting distributed objects at a predetermined node in a distributed system 失效
    在分布式系统中的预定节点处托管分布式对象的方法

    公开(公告)号:US06173313B2

    公开(公告)日:2001-01-09

    申请号:US09103546

    申请日:1998-06-24

    IPC分类号: G06F1516

    CPC分类号: G06F9/465

    摘要: A distributed object is hosted in a distributed system by invoking a global hash function on a generated name for the distributed object. The name for the distributed object is generated with knowledge of the global hash function so that the result of invoking the global hash function upon the name results in the selection of a predetermined node in the distributed system. The predetermined node may be selected based on the affinity of the node to the distributed object for reducing network messaging and communications overhead.

    摘要翻译: 分布式对象通过在分布式对象的生成名称上调用全局散列函数来托管在分布式系统中。 使用全局散列函数的知识生成分布式对象的名称,以便根据名称调用全局哈希函数的结果导致分布式系统中预定节点的选择。 可以基于节点对分布式对象的亲和度来选择预定节点,以减少网络消息和通信开销。

    Consistent read in a distributed database environment
    7.
    发明授权
    Consistent read in a distributed database environment 有权
    在分布式数据库环境中一致阅读

    公开(公告)号:US07334004B2

    公开(公告)日:2008-02-19

    申请号:US10119672

    申请日:2002-04-09

    IPC分类号: G06F17/30

    摘要: Techniques are provided for determining which data item version to supply to a query. According to the techniques, the determination is made by associating a new field, which indicates the time a data item version was current, with each data item version; associating a new field with each query, which indicates the last change that the query must see made by the transaction to which the query belongs; and determining which data item version to use to answer the query based, in part, on a comparison between the values of the two new fields.

    摘要翻译: 提供了用于确定要向查询提供哪些数据项版本的技术。 根据该技术,通过将表示数据项目版本当前的时间的新字段与每个数据项目版本相关联来进行确定; 将新字段与每个查询相关联,这表示查询必须看到该查询所属的事务所做的最后一次更改; 以及部分地基于两个新字段的值之间的比较来确定用于回答查询的数据项版本。

    Storing compression units in relational tables
    8.
    发明授权
    Storing compression units in relational tables 有权
    将压缩单元存储在关系表中

    公开(公告)号:US08645337B2

    公开(公告)日:2014-02-04

    申请号:US12769205

    申请日:2010-04-28

    IPC分类号: G06F7/00 G06F17/00 G06F17/30

    摘要: A database server stores compressed units in data blocks of a database. A table (or data from a plurality of rows thereof) is first compressed into a “compression unit” using any of a wide variety of compression techniques. The compression unit is then stored in one or more data block rows across one or more data blocks. As a result, a single data block row may comprise compressed data for a plurality of table rows, as encoded within the compression unit. Storage of compression units in data blocks maintains compatibility with existing data block-based databases, thus allowing the use of compression units in preexisting databases without modification to the underlying format of the database. The compression units may, for example, co-exist with uncompressed tables. Various techniques allow a database server to optimize access to data in the compression unit, so that the compression is virtually transparent to the user.

    摘要翻译: 数据库服务器将压缩单位存储在数据库的数据块中。 使用各种各样的压缩技术中的任一种,首先将表(或其多行的数据)压缩为“压缩单位”。 然后,压缩单元被存储在跨越一个或多个数据块的一个或多个数据块行。 结果,单个数据块行可以包括在压缩单元内编码的多个表行的压缩数据。 数据块中的压缩单元的存储与现有的基于数据块的数据库保持兼容,从而允许在预先存在的数据库中使用压缩单元,而无需修改数据库的底层格式。 压缩单元可以例如与未压缩的表共存。 各种技术允许数据库服务器优化对压缩单元中的数据的访问,使得压缩对于用户实际上是透明的。

    Techniques For Automatic Data Placement With Compression And Columnar Storage
    9.
    发明申请
    Techniques For Automatic Data Placement With Compression And Columnar Storage 有权
    用于压缩和柱状存储的自动数据放置技术

    公开(公告)号:US20120296883A1

    公开(公告)日:2012-11-22

    申请号:US13475669

    申请日:2012-05-18

    IPC分类号: G06F17/30

    摘要: For automatic data placement of database data, a plurality of access-tracking data is maintained. The plurality of access-tracking data respectively corresponds to a plurality of data rows that are managed by a database server. While the database server is executing normally, it is automatically determined whether a data row, which is stored in first one or more data blocks, has been recently accessed based on the access-tracking data that corresponds to that data row. After determining that the data row has been recently accessed, the data row is automatically moved from the first one or more data blocks to one or more hot data blocks that are designated for storing those data rows, from the plurality of data rows, that have been recently accessed.

    摘要翻译: 对于数据库数据的自动数据放置,维持多个访问跟踪数据。 多个访问跟踪数据分别对应于由数据库服务器管理的多个数据行。 当数据库服务器正常执行时,根据与该数据行相对应的访问跟踪数据,自动确定是否最近访问存储在第一个一个或多个数据块中的数据行。 在确定最近访问了数据行之后,数据行被自动从第一个或多个数据块移动到指定用于存储来自多个数据行的那些数据行的一个或多个热数据块,这些数据行具有 最近被访问。

    STRUCTURE OF HIERARCHICAL COMPRESSED DATA STRUCTURE FOR TABULAR DATA
    10.
    发明申请
    STRUCTURE OF HIERARCHICAL COMPRESSED DATA STRUCTURE FOR TABULAR DATA 审中-公开
    用于数据数据的分层压缩数据结构的结构

    公开(公告)号:US20120143833A1

    公开(公告)日:2012-06-07

    申请号:US13371354

    申请日:2012-02-10

    IPC分类号: G06F7/00

    CPC分类号: G06F16/221

    摘要: A highly flexible and extensible structure is provided for physically storing tabular data. The structure, referred to as a compression unit, may be used to store tabular data that logically resides in any type of table-like structure. According to one embodiment, compression units are recursive. Thus, a compression unit may have a “parent” compression unit to which it belongs, and may have one or more “child” compression units that belong to it. In one embodiment, compression units include metadata that indicates how the tabular data is stored within them. The metadata for a compression unit may indicate, for example, whether the data is stored in row-major or column major-format the order of the columns within the compression unit (which may differ from the logical order of the columns dictated by the definition of their logical container), a compression technique for the compression unit, the child compression units (if any), etc.

    摘要翻译: 提供了高度灵活和可扩展的结构,用于物理存储表格数据。 称为压缩单元的结构可用于存储逻辑上位于任何类型的类似桌面结构的表格数据。 根据一个实施例,压缩单元是递归的。 因此,压缩单元可以具有它所属的“父”压缩单元,并且可以具有属于它的一个或多个“子”压缩单元。 在一个实施例中,压缩单元包括指示表格数据如何被存储在其中的元数据。 压缩单元的元数据例如可以指示数据是以行主列还是列主格式存储在压缩单元内的列的顺序(其可以不同于由定义指定的列的逻辑顺序 的逻辑容器),压缩单元的压缩技术,子压缩单元(如果有的话)等等