Abstract: A method and apparatus are provided for retrieving documents from a collection of documents based on information other than the contents of a desired document. The collection of documents, which may be a hypertext system or documents available via the World Wide Web, is indexed. In one embodiment, an indexing process of a search engine receives one or more specifications that identify documents, or document locations, and non-content information such as a tag word or code word. The indexing process searches the index to identify all documents in the index that match one or more of the specifications. If a match is found, the tag word is added to the index, and information about the matching document is stored in the index in association with the tag word. A search query is submitted to the search engine. The search query is automatically modified to add a reference to the tag word, such as a query term that will exclude any index entry for a document associated with the tag word.

Abstract: Multiple memory access streams issued by multiple memory controller access devices are used for accessing DRAM or other memory. The memory controller can arbitrate among requests for multiple requestors, such as in a multiprocessor environment. Coherency can be provided by snooping a write buffer and returning, write buffer contents directly, in response to a read request for a matching address. Coherency need not be implemented through the entirety of an address space and preferably can be enabled for only selected portion or portions of the address space, reducing unnecessary coherency checking overhead.

Abstract: An approach for providing communications between mobile stations involves establishing a direct, digital communication link between mobile stations. A first mobile station determines a portion of a radio frequency (RF) band to carry communications between the first mobile station and a second mobile station. The first mobile station sends a request signal on the portion of the RF band to the second mobile station to request communications between the first mobile station and the second mobile station. The second mobile station transmits, in response to receiving the request signal, an acknowledge signal on the portion of the RF band directly to the first mobile station to acknowledge the request signal. The first mobile station establishes, in response to the acknowledge signal, a direct communications link between the first mobile station and the second mobile station.

Abstract: An approach for automatically determining database tables that are best suited for index tuning involves analyzing query performance data that specifies an average amount of time required to execute a plurality of queries on the database tables. One or more particular queries are selected from the plurality of queries based upon the query performance data. Data tables required to process the one or more particular queries are selected for index tuning.

Abstract: An approach for managing resources in a distributed computing system includes establishing dedicated process pools on nodes where work is to be performed. Each dedicated process pool is associated with a particular remote node and includes one or more processes. The one or more processes in each dedicated process pool perform work on behalf of processes on the associated remote node. Each dedicated process pool is managed by processes on the associated remote node using local synchronization data maintained on the associated remote node. The assignment of particular processes to perform work on behalf of processes on the associated remote node is performed by the processes on the associated remote node. In addition, the spawning of additional processes or the termination of existing processes from a dedicated process pool is managed by the processes on the associated remote node.

Abstract: An approach for storing and maintaining data involves determining whether data has been stored on a first non-volatile storage for a specified period of time. If so, then the data on the first non-volatile storage is deleted by overwriting the data on the first non-volatile storage with a predetermined value so that the data cannot be recovered. The first non-volatile storage is registered with a registration authority to provide authentication of the data maintained on the first non-volatile storage. A duplicate copy of the data is stored on a second non-volatile storage and if a determination is made that the data has been stored on a first non-volatile storage for a specified period of time, then the duplicate copy of the data is deleted by overwriting the duplicate copy of the data on the second non-volatile storage with the predetermined value.

Abstract: An approach for storing and maintaining data involves determining whether a first non-volatile storage has failed or otherwise encountered a problem. If so, then the data on the first non-volatile storage is deleted by overwriting the data on the first non-volatile storage with a predetermined value so that the data cannot be recovered. The first non-volatile storage is registered with a registration authority to provide authentication of the data maintained on the first non-volatile storage. A duplicate copy of the data is stored on a second non-volatile storage and if a determination is made that the first non-volatile storage has experienced a problem, then the duplicate copy of the data on the second non-volatile storage becomes active.

Abstract: A computer-implemented approach for reducing distortion in digital communications systems generally involves obtaining an optimal estimation of the original data using a Kalman filter with an increased length state to remove substantially all ISI in the time domain. The use of an increased length state in the Kalman filter provides a more accurate estimate of the transmitted data with relatively little additional computational cost. Subsequent equalization may also be performed in the frequency domain to correct any residual amplitude and phase distortion.

Abstract: A method and apparatus for reapplying changes to a database is disclosed. A recovery log is provided for recording all changes applied to the database so that the changes may be reapplied to the database during database recovery. Whenever a change is written to a storage device, the recovery log is updated to indicate that the particular change has been written to the storage device. During recovery, the data in the recovery log is sorted by file ID, data block ID, record type and version ID.

Abstract: A method and system for accessing a large object (LOB) that belongs to a cell in a table are provided. An index is built on a column in which the cell resides. The index has a key that includes a LOB identifier. A database server receives from a client a request to access the LOB. The server uses a LOB identifier value for the LOB to traverse the index to locate an index entry for the LOB. The server then follows address information contained in the index entry to a storage containing at least a portion of the LOB and accesses the portion of the LOB as specified in the request. A method and system for tracking storage for data items are also disclosed. Within an index that is built to access the data items are stored both index entries for locating blocks that store current versions of the data items, and index entries for locating blocks that store non-current versions of the data items.

Abstract: A method and an apparatus for managing access to data on a distributed database system is provided. A snapshot list is generated for a transaction executing on the distributed database system. The snapshot list specifies snapshot times for a plurality of locations in the distributed database system. The snapshot times are determined based upon the location of a data item and the location where the transaction is executing. The selection of a version of the data item to be provided to the transaction is made based upon the snapshot time for the location associated with the data.

Abstract: A method and apparatus are provided for processing reports. Upon system startup, a report server automatically starts one or more report processes. As client report commands are received from one or more client applications, the client report commands are assigned to one or more of the executing report processes. After a report is completed, the report process is automatically reinitialized and kept active to process another report. The report server automatically adjusts the number of active report processes based on the current report processing load requirements. According to another aspect of the present invention, a report queue is provided to store client report commands as they are received from the client applications. A report queue manager is also provided for externally managing the report queue.

Abstract: A method and apparatus that allow schema version evolution to occur without requiring applications that expect older schema versions to be recompiled is provided. According to one aspect of the invention, each application that requests data is supplied the data in the format that the application expects. To supply the data in the expected format, a mechanism is provided for tracking the evolution of data types without losing information. In addition, mechanisms are provided for determining the format expected by the application and the format in which the data is currently stored. A mechanism is also provided for converting the data from the stored format to the expected format when the two formats do not match. A data migration strategy is described in which data is gradually migrated to newer formats when the data is updated by applications that expect a more recent format than the format in which the data is currently stored.

Abstract: A method and apparatus for managing dependencies in a distributed environment to ensure the safety of remote procedure calls is disclosed. Each remote procedure call between a calling procedure and a target procedure includes an expected time stamp and expected signature associated with the target procedure. The expected time stamp contains the creation time of the target procedure at the time the calling procedure was last compiled. The expected signature contains data type information of the target procedure formal parameters at the time the calling procedure was last compiled. The target procedure compares the expected time stamp to an actual time stamp maintained by the target procedure. If the two time stamps do not match, the target procedure compares the expected signature and an actual signature maintained by the target procedure to determine whether the data types of the formal parameters sent by the calling procedure are compatible with the data types expected by the target procedure.

Abstract: A method and system for tracking storage for data items is provided. First, an index is built to access the data items. Then a first plurality of index entries for locating a first set of blocks are stored in the index, wherein blocks within the first set of blocks are blocks that store current first versions of the data items. Finally, a second plurality of index entries for locating a second set of blocks are stored in the index, wherein blocks within the second set of blocks are blocks that store non-current second versions of the data items.

Abstract: An approach for providing communication between sub-applications in a vertical application involves exchanging messages between sub-applications in a predetermined common message format referred to herein as a “common view.” Messages transmitted by sub-applications in message formats supported by the sub-applications are translated to produce messages in the common view. Messages to be received by sub-applications in the common view are translated to produce messages in the formats supported by the sub-applications. An adapter may be attached to each sub-application. The adapter provides for the translation of messages between a message format supported by the sub-application to which it is attached and the common view. An agent/broker architecture may be used in which agents are configured with metadata.

Abstract: A method and apparatus for processing reports is disclosed. After receiving a current report request, a duplicate job detection (DJD) key is generated based upon the current report request. The DJD key is then compared to DJD keys associated with previous report requests to determine whether the currently requested report has been previously requested. If the currently requested report has been previously requested, then a saved report generated in response to the previous report request is retrieved. Otherwise, a new report is generated based upon the current report request and then stored.

Abstract: A method and an apparatus for determining whether a transaction can use a version of a data item is provided. Transaction summary data is generated that is associated with one or more transactions that have updated a version of the data item. The transaction summary data specifies both a data buffer refresh time and a data buffer commit time. The data buffer refresh time is indicative of the latest time at which the version of data is guaranteed to be current. The data buffer commit time is indicative of the commit time of a most recently committed transaction from the one or more transactions that committed after updating the version of the data item. A determination is made, based upon the transaction summary data and a snapshot time used by the first transaction, whether the version of the data item is to be provided to the first transaction. The data buffer commit time is updated to reflect the commit time of other transactions that commit after updating the version of the data item.

Abstract: An approach for recovering after premature termination of a plurality of transactions involves: A) selecting a previously unselected transaction from the plurality of transactions; B) processing the selected transaction by undoing the lesser of a predetermined number of changes made by the selected transaction and all changes made by the selected transaction; and C) repeating steps A) and B) until all of the plurality of transactions have been processed. Another aspect of the approach involves: A) selecting a previously unselected transaction from the plurality of transactions, wherein the selected transaction is the previously unselected transaction from the plurality of transactions that made the fewest number of changes in the database; B) processing the selected transaction by undoing one or more changes in the database made by the selected transaction; and C) repeating steps A) and B) until all transactions from the plurality of transactions have been processed.

Abstract: An approach for representing polygons in an integrated circuit (IC) layout is provided. Polygons are represented by one or more wires, which in turn are each represented by one or more wire segments. Each wire segment is represented by a pair of directed line segments. A data structure hierarchy includes polygon data, wire data, wire segment data and branch data. The polygon data represents a set of IC devices to be represented in the IC layout. The wire data represents the wires that represent the polygons and specifies the associated wire segments and associated polygons. The wire segment data represents the wire segments and specifies the associated directed line segments for each wire segment that represent the wires and references the wire data. The branch data specifies connections between wires by specifying the connecting wire segments in the wires.