摘要:
Database management systems and program products that exploit time dependent sequential database management system processes to ensure presentation of the same data or view to one or a plurality of users through sequencing asynchronous database management operations such as recovery and replication. Sequencing is accomplished through the use of entries in sequential logs, including transaction logs, recovery logs, and other data recovery tools and applications. Uses include managing data migration and data replication.
摘要:
Systems, methods and articles of manufacture are disclosed for synchronizing a primary data system with an auxiliary data system that processes data for the primary data system. In one embodiment, how current the primary data system and the auxiliary data system are may be determined. Requests sent from the primary data system that were not processed by the auxiliary data system may be determined. The requests may be resent to the auxiliary data system for processing.
摘要:
An improved method for providing parallel apply in asynchronous data replication in a database system is disclosed. The improved method and system provides a high speed parallel apply of transactional changes to a target node such that the parallel nature of the application of changes does not compromise the integrity of the data. The method and system detects, tracks, and handles dependencies between transaction messages to be applied to the target node. If a transaction message has a dependency on one or more preceding transaction messages whose applications have not yet completed, that transaction message is held until the application completes. In addition, the method and system requires significantly less overhead than conventional approaches.
摘要:
A computer readable medium encoded with a computer program for handling transaction messages in asynchronous data replication in a database system is disclosed. The computer program provides a high speed parallel apply of transactional changes to a target node such that the parallel nature of the application of changes does not compromise the integrity of the data. The computer program detects, tracks, and handles dependencies between transaction messages to be applied to the target node. If a transaction message has a dependency on one or more preceding transaction messages whose applications have not yet completed, that transaction message is held until the application completes. In addition, the computer program requires significantly less overhead than conventional approaches.
摘要:
A method and system for asynchronously replicating data changes in a database system captures update information for a data update in a source table from a database log, where the data value from the data update is not in the database log. A query is built to obtain the data value from the source table using the update information, including a key column value that identifies the row of the source table in which the data resides. When the key column is also updated in the same or different transaction, the data update information is stored, and the updated key column value is replaced with a later captured key column update value. The query is built and executed, and the data update is replicated at a target table. In this manner, data objects whose values are not recorded in a database log can be asynchronously replicated in a database system.
摘要:
A callback to a data manager is carried out from an index manager in a query processing system for an index-data fetch to enable an index page held stabilized by an index manager to remain stabilized during predicate checking or data consumption operations. The index manager locates a data identifier in an index and calls back to a data manager to access the data indicated by the data identifier. The data manager may carry out a predicate check or a data consuming operation on the data and if this is the case the index manager may access the next data identifier in the index when the data manager callback is complete. The index page need not be destabilized in such a case.
摘要:
Methods and related apparatus, for use in programming language systems, are set forth which support compile-time type checking for overloaded functions in an environment supporting subtypes with multiple inheritance. At both compile and runtime, the invention considers the type of all actual arguments of a function to select a proper function instance to execute. Furthermore, the methods contemplated by the invention identify at compile time the set of function instances which might be invoked due to subtype substitutions for the actual arguments. Since type errors on function invocations or variable assignments are usually indicative of a programming error, program reliability can be improved and faults that would otherwise result in runtime errors can be corrected through the use of the invention prior to program deployment.
摘要:
Techniques are disclosed for synchronizing a primary data system with an auxiliary data system that processes data for the primary data system. In one embodiment, how current the primary data system and the auxiliary data system are is determined. Requests sent from the primary data system that were not processed by the auxiliary data system are determined. The requests are resent to the auxiliary data system for processing.
摘要:
Provided are techniques for partitioning a physical index into one or more physical partitions; assigning each of the one or more physical partitions to a node in a cluster of nodes; for each received document, assigning an assigned-doc-ID comprising an integer document identifier; and, in response to assigning the assigned-doc-ID to a document, determining a cut-off of assignment of new documents to a current virtual-index-epoch comprising a first set of physical partitions and placing the new documents into a new virtual-index-epoch comprising a second set of physical partitions by inserting each new document to a specific one of the physical partitions in the second set using one or more functions that direct the placement based on one of the assigned-doc-id, a field value derived from a set of fields obtained from the document, and a combination of the assigned-doc-id and the field value.
摘要:
Database management systems, methods, and program products that exploit time dependent sequential database management system processes to ensure presentation of the same data or view to one or a plurality of users through sequencing asynchronous database management operations such as recovery and replication. Sequencing is accomplished through the use of entries in sequential logs, including transaction logs, recovery logs, and other data recovery tools and applications. Uses include managing data migration and data replication.