Using global temporary tables to transform queries
    1.
    发明授权
    Using global temporary tables to transform queries 有权
    使用全局临时表来转换查询

    公开(公告)号:US06684203B1

    公开(公告)日:2004-01-27

    申请号:US09436053

    申请日:1999-11-08

    IPC分类号: G06F1730

    摘要: A technique and mechanism for transforming a query is described. A given query is transformed into a transformed query that references a global temporary table. Specifically, the given query contains a join between a given table and one or more other tables referenced by constraints (e.g. predicates). References to one or more of the constrained tables are replaced by a reference to a global temporary table. Before executing the transformed query, data that satisfies the constraints placed on the constrained table is inserted into the global temporary table.

    摘要翻译: 描述了用于转换查询的技术和机制。 给定的查询被转换为引用全局临时表的转换查询。 具体来说,给定的查询包含一个给定表和一个或多个由约束引用的其他表(例如谓词)之间的连接。 对一个或多个受约束的引用由对全局临时表的引用替代。 在执行转换查询之前,将满足约束表上约束的数据插入到全局临时表中。

    Finding the TOP N values through the execution of a query
    2.
    发明授权
    Finding the TOP N values through the execution of a query 有权
    通过执行查询查找TOP N值

    公开(公告)号:US06546382B1

    公开(公告)日:2003-04-08

    申请号:US09433827

    申请日:1999-11-03

    IPC分类号: G06F1730

    摘要: A method and mechanism is provided for executing a query that includes a subquery, where the subquery includes an ORDER BY clause. The results generated by executing the subquery are ordered as specified by the ORDER BY clause. When the results of the subquery are referenced by the outer query, the results generated for the subquery satisfy the restriction. For example, the restriction may specify that the row number pseudo-column be less than a threshold. In response, a TOP N operation is performed to return the rows that are TOP N in order. The order is based on the ORDER BY clause.

    摘要翻译: 提供了一种方法和机制,用于执行包含子查询的查询,其中子查询包含ORDER BY子句。 通过执行子查询生成的结果按照ORDER BY子句的指定进行排序。 当子查询的结果由外部查询引用时,为子查询生成的结果满足限制。 例如,限制可以指定行号伪列小于阈值。 作为响应,执行TOP N操作以依次返回TOP N的行。 该订单基于ORDER BY子句。

    Method for executing star queries
    3.
    发明授权
    Method for executing star queries 失效
    执行星型查询的方法

    公开(公告)号:US5848408A

    公开(公告)日:1998-12-08

    申请号:US808621

    申请日:1997-02-28

    IPC分类号: G06F17/30

    摘要: A method and apparatus for processing star queries is provided. According to the method, a star query is transformed by adding to the star query subqueries that are not in the query. The subqueries are generated based on join predicates and constraints on dimension tables that are contained in the original query. The subqueries are executed, and the values returned by the subqueries are used to access one or more bitmap indexes built on columns of the fact table. The bitmaps retrieved for the values returned by each subquery are merged to create one subquery bitmap per subquery. An AND operation is performed on the subquery bitmaps, and the resulting bitmap is used to determine which data to retrieve from the fact table.

    摘要翻译: 提供了一种处理星型查询的方法和装置。 根据该方法,通过添加到不在查询中的星型查询子查询来转换星型查询。 子查询是基于原始查询中包含的维表上的连接谓词和约束生成的。 执行子查询,子查询返回的值用于访问一个或多个基于事实表列的位图索引。 为每个子查询返回的值检索的位图被合并,以便为每个子查询创建一个子查询位图。 在子查询位图上执行AND操作,并且生成的位图用于确定从事实表中检索哪些数据。

    Parallel distinct aggregates
    4.
    发明授权
    Parallel distinct aggregates 有权
    平行不同的聚集体

    公开(公告)号:US06430550B1

    公开(公告)日:2002-08-06

    申请号:US09455004

    申请日:1999-12-03

    IPC分类号: G06F1730

    摘要: Techniques are provided for executing distinct aggregation operations in a manner that is more scalable and efficient than prior techniques. A three-stage technique is provided to parallelize aggregation operations that involve both grouping and multiple distinct-key columns. Such queries are handled by splitting rows into as many pieces as there are distinct aggregates in the query, and processing the row pieces. During the first-stage, a set of slave processes scans the rows of the base tables and performs partial duplicate elimination. During the second-stage, a set of slave processes completes the duplicate elimination and performs partial set function aggregation. During the third-stage, a third set of slave processes completes the set aggregation to produce the results of the distinct aggregation operation. In addition, two-stage parallelization techniques are provided for parallelizing single-distinct aggregations, and for parallelizing distinct aggregation operations that involve multiple distinct-key columns, but do not require grouping.

    摘要翻译: 提供技术用于以比现有技术更可扩展和有效的方式执行不同的聚合操作。 提供了三阶段技术来并行化并行化涉及分组和多个不同键列的聚合操作。 这样的查询是通过将行拆分成与查询中有不同的聚合一样多的部分来处理的,并处理这些行。 在第一阶段,一组从属进程扫描基表的行,并执行部分重复消除。 在第二阶段,一组从属进程完成重复消除,并执行部分集合功能聚合。 在第三阶段,第三组从属进程完成集合聚合以产生不同聚合操作的结果。 此外,还提供了两级并行化技术,用于并行化单个不同的聚合,并且用于并行化涉及多个不同密钥列的不同聚合操作,但不需要进行分组。

    SQL Execution Plan Baselines
    5.
    发明申请
    SQL Execution Plan Baselines 有权
    SQL执行计划基准

    公开(公告)号:US20090106306A1

    公开(公告)日:2009-04-23

    申请号:US12188678

    申请日:2008-08-08

    IPC分类号: G06F17/30

    CPC分类号: G06F17/30469 G06F17/30463

    摘要: Approaches, techniques, and mechanisms are disclosed for maintaining a set of baseline query plans for a database command. Except in rare circumstances, a database server may only execute a command according to a baseline plan, even if the database server predicts that a different plan has a lower cost. The set of baseline plans are plans that, for one reason or another, have been determined to provide acceptable actual performance in at least one execution context. When the database server receives a request to execute a particular command, the database server, if possible, always executes the command according to the lowest predicted cost baseline plan. The database server may evolve the plan baseline to include additional plans by generating and testing new plans in response to new requests to execute the database command, or as part of a query optimization or tuning process.

    摘要翻译: 披露了用于维护数据库命令的一组基线查询计划的方法,技术和机制。 除极少数情况下,数据库服务器只能根据基准线执行命令,即使数据库服务器预测不同的计划成本较低。 一组基准计划是由于某种原因决定在至少一个执行环境中提供可接受的实际绩效的计划。 当数据库服务器接收到执行特定命令的请求时,如果可能,数据库服务器总是根据最低预测成本基线计划执行该命令。 数据库服务器可以通过生成和测试新计划以响应执行数据库命令的新请求,或作为查询优化或调整过程的一部分,来演进计划基准以包括额外的计划。

    Creating bitmaps from multi-level identifiers
    6.
    发明授权
    Creating bitmaps from multi-level identifiers 失效
    从多级标识符创建位图

    公开(公告)号:US06081800A

    公开(公告)日:2000-06-27

    申请号:US807344

    申请日:1997-02-28

    IPC分类号: G06F17/30

    摘要: A method and apparatus for generating and using bitmaps in a database system that employs multi-level identifiers is provided. The generated bitmaps include bits that correspond to the identifiers that have been assigned to existing records, as well as bits that correspond to all intervening multi-level identifiers that have not yet been assigned. Therefore, when new rows are inserted into the table associated with the bitmap, new bits do not have to be inserted into the existing bitmap. When existing rows are deleted, the bits that correspond to the deleted rows are not themselves deleted, but are simply set to a value that indicates that the corresponding row does not satisfy the criteria associated with the bitmap.

    摘要翻译: 提供了一种在采用多级标识符的数据库系统中生成和使用位图的方法和装置。 生成的位图包括对应于已经分配给现有记录的标识符的位以及对应于尚未被分配的所有中间多级标识符的位。 因此,当将新行插入到与位图关联的表中时,新位不必插入到现有位图中。 当现有行被删除时,对应于被删除行的位本身不被删除,而是被简单地设置为指示相应行不满足与位图相关联的标准的值。

    SQL execution plan baselines
    8.
    发明授权
    SQL execution plan baselines 有权
    SQL执行计划基线

    公开(公告)号:US09189522B2

    公开(公告)日:2015-11-17

    申请号:US12188678

    申请日:2008-08-08

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

    CPC分类号: G06F17/30469 G06F17/30463

    摘要: Approaches, techniques, and mechanisms are disclosed for maintaining a set of baseline query plans for a database command. Except in rare circumstances, a database server may only execute a command according to a baseline plan, even if the database server predicts that a different plan has a lower cost. The set of baseline plans are plans that, for one reason or another, have been determined to provide acceptable actual performance in at least one execution context. When the database server receives a request to execute a particular command, the database server, if possible, always executes the command according to the lowest predicted cost baseline plan. The database server may evolve the plan baseline to include additional plans by generating and testing new plans in response to new requests to execute the database command, or as part of a query optimization or tuning process.

    摘要翻译: 披露了用于维护数据库命令的一组基线查询计划的方法,技术和机制。 除极少数情况下,数据库服务器只能根据基准线执行命令,即使数据库服务器预测不同的计划成本较低。 一组基准计划是由于某种原因决定在至少一个执行环境中提供可接受的实际绩效的计划。 当数据库服务器接收到执行特定命令的请求时,如果可能,数据库服务器总是根据最低预测成本基线计划执行该命令。 数据库服务器可以通过生成和测试新计划以响应执行数据库命令的新请求,或作为查询优化或调整过程的一部分,来演进计划基准以包括额外的计划。

    Method and mechanism for storing and accessing data
    9.
    发明授权
    Method and mechanism for storing and accessing data 有权
    存储和访问数据的方法和机制

    公开(公告)号:US07103608B1

    公开(公告)日:2006-09-05

    申请号:US10144689

    申请日:2002-05-10

    IPC分类号: G06F17/30 G06F7/00 G06F12/02

    摘要: A method and mechanism is disclosed for implementing storage and retrieval of data in a computing system. Data compression is performed on stored data by reducing or eliminating duplicate values in a database block. Duplicated values are eliminated within the set of data that is to be stored within a particular data storage unit. Rather than writing the duplicated data values to the data storage unit, the on-disk data is configured to reference a symbol table a single copy of each duplicated data value. Column reordering may be performed in an embodiment to further improve compression efficiency. The column reordering may be performed to allow efficient removal of trailing NULL values from on-disk storage.

    摘要翻译: 公开了一种用于在计算系统中实现数据的存储和检索的方法和机制。 通过减少或消除数据库块中的重复数据,对存储的数据执行数据压缩。 在要存储在特定数据存储单元内的数据集合内消除重复的值。 将盘上数据值写入到数据存储单元中,而不是将该盘上数据配置成将每个复制的数据值的单个副本引用到符号表中。 可以在一个实施例中执行列重排序以进一步提高压缩效率。 可以执行列重新排序,以便有效地从磁盘存储中删除尾随的NULL值。

    Indexing key ranges
    10.
    发明授权
    Indexing key ranges 有权
    索引键范围

    公开(公告)号:US06658405B1

    公开(公告)日:2003-12-02

    申请号:US09478945

    申请日:2000-01-06

    申请人: Cetin Ozbutun

    发明人: Cetin Ozbutun

    IPC分类号: G06F1730

    摘要: A method and mechanism is described for indexing a body of records. An index associates ranges with records that hold key field values that fall within those ranges. Such an index may be implemented as a bitmap index. The bitmap index may contain entries that associate a range with a bitmap. The bitmap of an index entry identifies which records have a key field value that falls within the range associated with the entry. The index may be a native index maintained by a database system. The database system uses the index to efficiently process queries that specify range criteria.

    摘要翻译: 描述了一种用于索引记录体的方法和机制。 索引将范围与保存在该范围内的关键字段值的记录相关联。 这样的索引可以被实现为位图索引。 位图索引可能包含将范围与位图相关联的条目。 索引条目的位图标识哪些记录具有属于与条目关联的范围内的关键字字段值。 索引可以是由数据库系统维护的本机索引。 数据库系统使用索引来有效地处理指定范围标准的查询。