Abstract: A method and apparatus for distributing work granules of a parent task among processes running on various nodes in a multi-processing computer system is provided. The parent task is divided into work granules of varying sizes based on the location of the data that must be accessed to perform the work granules. At least one process on each of the nodes that will be assisting in the execution of the parent task is initially assigned a work granule based on efficiency considerations. Such efficiency considerations may include, for example, the location of the data to be accessed relative to the process, the current I/O load of the devices on which data to be accessed is stored, and the relative sizes of the various work granules. When a process completes the work granule assigned to it, the process is assigned one of the remaining unassigned work granules. Again the work granule assignment is made based on efficiency considerations. This process continues until all of the work granules have been completed.

Abstract: A pluggable tablespace is enabled by logically partitioning a database into a set of tablespaces and storing all of the tablespaces disk pointers in tablespace-relative format. A pluggable set of tablespaces is unplugged by exporting the associated metadata, and making a binary copy of the tablespaces. The pluggable set of tablespaces is plugged into a target database by making the pluggable set accessible to the target database and importing the associated metadata, without patching any of the disk pointers.

Abstract: A system is provided for resetting a process from a first activity to a second activity, in which the second activity was previously performed. The system identifies activities that were previously performed after the second activity. Each identified activity (including the second activity) is then executed in a cancel mode of operation. The execution of the activities is performed sequentially from the first activity to the second activity. The system then executes the second activity in a run mode of operation. The cancel mode of operation cancels the changes that were implemented by a particular activity during a previous execution of the activity. The activities can maintain information regarding the last change implemented by the activity, which is used by the activity in the cancel mode of operation to cancel the last change implemented by the activity. The system may include a loop reset counter associated with the first activity and the second activity.

Abstract: A content processing system determines content of input discourse. The content processing system includes a theme vector processor that determines themes in the input discourse. The theme vector processor identifies themes, including identifying the relative importance of the themes in the input discourse by generating a theme strength. The theme strength indicates relative thematic importance for the theme in the input discourse. A knowledge catalog, which includes static ontologies arranged in a hierarchical structure, is also disclosed. The static ontologies are independent and parallel of each other, and contain knowledge concepts to represent a world view of knowledge. The theme vector processor utilizes the static ontologies to generate a theme concept for each theme by extracting a knowledge concept from a higher level node in the hierarchical structure of a static ontology.

Abstract: A method and apparatus for updating a segmented bitmapped index to reflect a change made to data upon which the segmented index is based. Change records specifying changes to bitmap segments contained in the segmented bitmapped index are sorted by key value (bitmap segment) and row ID (bit) before being applied to the segmented bitmapped index. When the change records are being applied to the bitmap segment contained in the segmented bitmapped index, the index entry containing the bitmap segment to be updated is locked. If a new bitmap segment must be generated, the index entry covering a row in the data having a row ID less than the row ID of the change is first locked. Then a new index entry is generated, stored in the segmented bitmapped index, and the locked index entry unlocked.

Abstract: A database synchronizer facilitates computing systems which have client-side and server-side applications that share data in similar database structures, but which do not maintain a continuous connection to a single shared data source. In general, a database synchronizer is used to share data among many nodes on the computing system. The database synchronizer is used to synchronize the data in a central database for a particular client with the data on that client's intermittently-connected computer. Updates performed by either client or server are propagated to the other side when a connection is established and eventually from the server to other clients in the system.

Abstract: A data transport system has application for transferring binary large objects (blobs) to one or more clients. The data transport system includes a mass storage device, a high bandwidth network, a blob server and an applications server. The blobs are pre-packetized in a general format compatible with a network protocol in that the packets do not include specific control information that identifies a particular client and a particular request for a blob. At run time, a requesting client generates a request to the applications server to request a blob stored in the mass storage device. In turn, the applications server generates a request, that includes control information to identify the requesting client and the particular request, to the blob server. The blob server accesses the mass storage device to retrieve packets corresponding to the blob requested, and transfers the packets and the control information from the blob server to the requesting client.

Abstract: A method and system for estimating a cost of using a tree index to process a query that includes at least one interval restriction is provided. The cost of using an index to process a select query is estimated by (1) classifying intervals covered by the index as either true, false, or mixed intervals, based on the selection criteria, (2) estimating the cost of using the index based on the size of the true and mixed intervals, and (3) improving the cost estimate based on the average ratio of the parent and child node cardinalities taken down one or more sampling paths of the index. Use of a pseudo-ranked B-tree is generally preferred over a fully ranked tree due to the relatively low update costs of a pseudo-ranked B-tree. The index cost estimations are used to pick a select query execution plan that has the smallest cost, in terms of disk I/O operations, from numerous possible execution plans.

Abstract: A method for managing termination of a process that holds a resource lock on behalf of another process is described. A first process acquires a first lock to a resource on behalf of a second process to exclude other processes from accessing the resource. The second process then acquires a wait lock to the resource. Later, when a third process acquires the first lock to the resource, the third process determines whether the first process terminated without releasing the lock. If the first process did terminate without releasing the lock, the third process attempts to acquire the wait lock. In attempting to acquire the wait lock, execution of the third process is suspended until the second process releases the wait lock. Consequently, acquisition of the wait lock by the third process prevents concurrent access to the resource by the third process and the second process.

Abstract: A method and apparatus for backing up and restoring data to a database is provided. During the backup, data blocks are copied from a database to a storage medium without the contents of the data blocks being analyzed during the copy. Data indicating the initial configuration of the data blocks is also backed up. During the restore, the data blocks are copied from the storage medium back to the database. The information within each copied data block is analyzed to identify any location dependent information (e.g., pointers). All location dependent information is updated based on the initial configuration and the new configuration to cause the location dependent information to reflect the new configuration.

Abstract: A method and apparatus for determining whether a particular version of a data item may be used by a transaction are provided. To determine whether the particular version may be used by the transaction, a MUST-SEE set associated with the transaction is compared to an EXCLUDED set associated with the particular version, and a CANNOT-SEE set associated with the transaction is compared to an INCLUDED set associated with the particular version. The MUST-SEE set includes all transactions that have made updates that must be seen by the transaction. The EXCLUDED set includes all transactions that have made updates to the data item that have been removed from the particular version of the data item and all transactions that will make changes to the data item in the future. The CANNOT-SEE set includes all transactions that have made updates that cannot be seen by the transaction. The INCLUDED set includes all transactions that have made updates that are reflected in the particular version of the data item.

Abstract: A pluggable tablespace is enabled by logically partitioning a database into a set of tablespaces. A pluggable set of tablespaces is stored on a transportable medium in which all the disk pointers of the pluggable set is stored in tablespace-relative format. In addition, the pluggable set includes exported associated metadata about objects contained in the pluggable set. The pluggable set is plugged into a target database by making the pluggable set accessible to the target database and importing the associated metadata, without patching any of the disk pointers.

Abstract: A geometry management system provides an initial bottom-up layout that determines the ideal and default sizes of objects including the pages, views, and frame windows. The geometry management system further includes a top down configuration to handle resizing of a window including the objects contained in the window. The geometry management system includes geometry manager objects, container objects, and child objects. At design or layout time, the child objects are placed in a parent container via a drag and drop operation. The geometry management system specifies size parameters through negotiation among the child objects, the containers, and the high level geometry manager. When a child object requires resizing, the child object requests geometry from the parent container object. Based on the specified parameters, the container determines whether a given geometry is feasible. If the parameters are acceptable, the container implements the geometry.

Abstract: A method and apparatus for parallelizing operations that change a database is provided. A coordinator process receives a statement that requires data to be written into the database. In response to the statement, the coordinator process assigns granules of work to multiple processes. Each of the multiple processes executes the granule of work by writing to the database a distinct portion of the set of data that is to be added to the database. The various portions of data are then merged to create the set of data to be added to the database.

Abstract: A method and system are provided for processing records from a set of records, where records are repeatedly being added to the set of records, and where each record in the set of records has to be processed once for each of a plurality of entities. According to the method, each record that is added to the set of records is marked with a default batch value. For each entity of the plurality of entities, a batch of the records is processed by performing the steps of: reading a last batch value associated with the entity, processing the records in the set of records that are marked with batch values that are more recent than the last batch value associated with the entity, and updating the last batch value associated with the entity to a most recent batch value of the records processed for the entity.

Abstract: A method and system are provided for duplicating at a destination site changes made to data at a source site. According to the method a plurality of streams are established between the source site and the destination site. The plurality of streams are used in parallel to propagate changes made at the source site to the destination site. A record of transactions that made changes that need to be propagated from the source site to the destination site is maintained at the source site. Before propagating changes made by a transaction to the destination site on a stream of the plurality of streams, the record of transactions is inspected to identify a set of transactions whose changes are not known to have been made permanent at the destination site. It is then determined whether the transaction could possibly depend on any transaction in the set of transactions.

Abstract: A method and system for providing isolation levels in a database system is provided. A serializable isolation level is provided by causing all statements in a transaction to see a "snapshot" of the database. A snapshot includes only those changes made to the database by a particular set of transactions. For example, the snapshot for a given transaction may include only the changes made by transactions that committed prior to the execution of the given transaction. The set of all transactions whose changes are included in a particular snapshot of the database is referred to as the snapshot set. Concurrently executing transactions may update the database while a serializable transaction is being executed. Updates that are not included in the snapshot of the serializable transaction are undone prior to processing each statement in the serializable transaction to recreate the data as it existed in the snapshot.

Abstract: A database synchronizer facilitates computing systems which have client-side and server-side applications that share data in similar database structures, but which do not maintain a continuous connection to a single shared data source. In general, a database synchronizer is used to share data among many nodes on the computing system. The database synchronizer is used to synchronize the data in a central database for a particular client with the data on that client's intermittently-connected computer. Updates performed by either client or server are propagated to the other side when a connection is established and eventually from the server to other clients in the system.

Abstract: A database synchronizer facilitates computing systems which have client-side and server-side applications that share data in similar database structures, but which do not maintain a continuous connection to a single shared data source. In general, a database synchronizer is used to share data among many nodes on the computing system. The database synchronizer is used to synchronize the data in a central database for a particular client with the data on that client's intermittently-connected computer. Updates performed by either client or server are propagated to the other side when a connection is established and eventually from the server to other clients in the system.

Abstract: A method and apparatus for use in a digital video delivery system is provided. A digital representation of an audio-visual work, such as an MPEG file, is parsed to produce a tag file. The tag file includes information about each of the frames in the audio-visual work. During the performance of the audio-visual work, data from the digital representation is sent from a video pump to a decoder. Seek operations are performed by causing the video pump to stop transmitting data from the current position in the digital representation, and to start transmitting data from a new position in the digital representation. The information in the tag file is inspected to determine the new position from which to start transmitting data. To ensure that the data stream transmitted by the video pump maintains compliance with the applicable video format, prefix data that includes appropriate header information is transmitted by said video pump prior to transmitting data from the new position.