摘要:
A database management system includes an execution engine that, upon rollback of an aborted transaction, has the ability to set fields of the rows that are updated or deleted by the transaction prior to aborting. In particular, when a select, update or delete statement includes a “set on rollback” clause, the respective table access operator of the execution engine modifies the “before image” of each row that is stored by the transaction log manager. The modified before image includes the field updates specified by the set on rollback clause. If a transaction associated with the statement aborts, when the transaction log manager restores the before images of each row that was deleted or updated by the transaction, the restored before images include the field updates specified by the set on rollback clause.
摘要翻译:数据库管理系统包括一个执行引擎,在中止事务的回滚之后,能够在中止之前设置事务更新或删除的行的字段。 特别地,当select,update或delete语句包括“set on rollback”子句时,执行引擎的相应表访问操作符修改由事务日志管理器存储的每一行的“before image”。 修改后的图像包括由rollback子句中指定的字段更新。 如果与该语句关联的事务中止,则当事务日志管理器恢复由事务删除或更新的每一行的先前图像时,恢复的映像之前包括由rollback子句设置的字段更新。
摘要:
There is provided a computer-executed method of freeing memory. One exemplary method comprises receiving a message from a user process. The message may specify a virtual address for a memory segment. The virtual address may be mapped to the memory segment. The memory segment may comprise a physical page. The method may further comprise identifying the physical page based on the virtual address. Additionally, the method may comprise freeing the physical page without unmapping the memory segment.
摘要:
A method and system to automate software testing using sniffer side and browser side recording and a toolbar interface are described. In one embodiment, a system tests programming code associated with a website and creates a first test case. In another embodiment, the system includes a testing device having a test interface to enable a user to initiate a first test case and to store a first HTML representation and a first XML representation of encrypted web pages viewed during the first test case. In another embodiment, the system includes a sniffer server that operates as a proxy server for the website and stores a second HTML representation and a second XML representation of unencrypted web pages viewed during the first test case. The system may include a hosting server that hosts the website and receives the first and the second HTML and XML representations from the testing device and the sniffer server when the test case is terminated via the test interface.
摘要:
A method and system to reduce false positives within an automated software-testing environment using a comparator module, a filter application module, and a preview generator module is provided. In one exemplary embodiment, a method within a testing system for testing web pages associated with a current version website by automatically generating filter data by comparing differences between a plurality of iterations of a test case executed on a previous version website, automatically generating error data by executing the test case on the current version website, and detecting differences between the previous version and the current version of the website by applying filtering rules within the filter data to the error data to remove false positives.
摘要:
A structured query language (SQL) grouping and aggregation system and method that incorporates hash-based techniques, several overflow handling strategies and statistics-based process-selection criteria. The method can execute SQL group-by queries on distributed database tables or tables stored locally to the database management system (DBMS) processor executing the grouping method. Hash-based techniques allow groupings and aggregates to be generated on the fly through the use of partial aggregates maintained in primary memory. Where primary memory is limited, groups and aggregates are still generated for as many groups as can be maintained in primary memory, while various overflow procedures are provided for buffering ungrouped data and writing that data to an overflow disk file for later processing. In one overflow procedure, raw data from groups that cannot be aggregated in primary memory are buffered then written to the overflow disk file. In a second overflow procedure, ungroupable raw data is formatted the same as data being aggregated in the group table, buffered, and then written to the overflow file. In a third overflow procedure, ungroupable raw data is partially aggregated in an output buffer maintained in primary memory before being written to the overflow file maintained in secondary memory. Database table statistics maintained by a cataloger are consulted to determine whether hash-based grouping or conventional sort based grouping should be used to execute a group-by query. The system is adaptable to running a grouping query against a partitioned database on distributed processors.
摘要:
A system and method for providing parallel result streams for database queries is provided. The system includes a network including a client, a server, and a database. The client executes an application and sends a query to the server. In response, the server compiles the query to produce a query plan, executes statements in the query plan and sends parallel result streams to the client.
摘要:
An automated method to align column values to proper byte boundaries for rapid scanning in a parallel processing database system. A table definition is received having a logical order of fields. The fields are re-ordered to create a physical order of fields. The physical order of fields has fixed length fields having a same byte alignment requirement positioned adjacent to each other in descending order from largest size to smallest size, and wherein a first fixed length field in the physical order is aligned on a proper byte boundary. Other embodiments, aspects and features are also disclosed.
摘要:
A method and system to automate software testing using sniffer side and browser side recording and a toolbar interface are described. In one embodiment, a system tests programming code associated with a website and creates a first test case. In another embodiment, the system includes a testing device having a test interface to enable a user to initiate a first test case and to store a first HTML representation and a first XML representation of encrypted web pages viewed during the first test case. In another embodiment, the system includes a sniffer server that operates as a proxy server for the website and stores a second HTML representation and a second XML representation of unencrypted web pages viewed during the first test case. The system may include a hosting server that hosts the website and receives the first and the second HTML and XML representations from the testing device and the sniffer server when the test case is terminated via the test interface.
摘要:
There is provided a computer-implemented method of modifying a query executing in a database management system. The method comprises sending a no-wait message for the query to a control broker. The method also comprises receiving a reply to the no-wait message from the control broker. The reply to the no-wait message specifies a modification to the query. Additionally, the method comprises performing the modification.
摘要:
A system and method for providing parallel result streams for database queries is provided. The system includes a network including a client, a server, and a database. The client executes an application and sends a query to the server. In response, the server compiles the query to produce a query plan, executes statements in the query plan and sends parallel result streams to the client.