Abstract: A method of checkpointing and restarting processes that share a file that is open begins with a step of assigning a priority to one of the processes that share the file. This identifies a priority process. The method concludes with a step of reopening the file when restoring the priority process.

Abstract: A method and system for ranking objects based on relationships with objects of a different object type is provided. The ranking system defines an equation for each attribute of each type of object. The equations define the attribute values and are based on relationships between the attribute and the attributes associated with the same type of object and different types of objects. The ranking system iteratively calculates the attribute values for the objects using the equations until the attribute values converge on a solution. The ranking system then ranks objects based on attribute values.

Abstract: To analyze a data set having a one-to-many relation, the number of simultaneous occurrences of data in which two data elements are coexistent is obtained for all combinations of two data elements. A dependence ratio of one data element upon the other data element is calculated from the numbers of simultaneous occurrences. The data elements are grouped based upon the numbers of occurrences of individual data elements and the dependence ratios compared with the predetermined thresholds. Based on the number of occurrences of individual data elements and the dependence ratios, subordinate relations of data elements within the same group are specified and displayed to a user in the form of a tree or balloon figure.

Abstract: A method for using pre-computed information stored in auxiliary structures to speed up processing of expensive queries on hierarchical documents such as XML documents being queried using XPath. The invention defines a taxonomy of such structures such as indexes and materialized views for storing pre-computed XPath results (PXRs), determines what portion of the query can be evaluated by the structures, and computes the compensation for the results generated by the structures. The invention detects all structures applicable to the query and rewrites the query to use such structures, speeding up the performance of the queries. The invention identifies the matching structures by detecting containment mappings between XPath expressions in the query and the structure. The invention also includes a new representation for XPath expressions that is rich enough to express all features of XPath.

Abstract: One embodiment of the invention employs techniques for providing a default object-relational mapping between persistent data objects (i.e., the objects that represent persistent data from a database) and a relational database. In a Java environment, for example, each entity bean is mapped to a particular database table, and each of the persistent fields within the entity bean are mapped to columns of the database table. Relationships between entity beans are expressed as mappings between primary keys and foreign keys within the database schema. Dependent-value persistent fields may be mapped to multiple columns or to a single column of a special Java type (java.sql.Types. BLOB). In addition, one embodiment of the invention generates a default database schema using the default O/R mapping by executing a series of SQL commands generating the tables and columns.

Abstract: A method and system for synchronizing objects among members of a replica set. Objects on members of the replica set are quickly synchronized via a join algorithm that takes advantage of version vectors. When an object is deleted, the object is tombstoned (i.e., marked as “dead”). Tombstones are also replicated between the connected members of the replica set. After a period of time (e.g., a timeout), the tombstones are deleted. A slow sync algorithm executes periodically to ensure that objects that were not deleted via replicated tombstones are eventually deleted. An époque algorithm provides that members that have been offline for a long period of time will update their objects before they participate in a join synchronization.

Abstract: An architecture for efficiently identifying the scope and timeframe of database errors, providing online history images, creating online point-in-time views of application tables, reconstructing equivalent SQL statements of a committed transaction or of a user session, providing a selective audit trail report on demand, and permitting selective online rollbacks in an application database. The rollback can be done on a single row, a single transaction, a group transactions, a user session, or all user tables. The system includes after images tables and before images tables and tracks all before images of user application tables when a user performs an INSERT, UPDATE, or DELETE operation with respect to a row in a table. Also, the system is provided to generate history images of application tables at a point-in-time, and to selectively rollback, or undo whole or a portion of application tables, to generate a selective audit trail report on demand, and to manage the before images.

Abstract: A backup method is provided for backing up a data base of an additional storage type that added data is not updated and deleted. An attribute of data update refusal, i.e., an attribute of only data reference permission is set to each storage area in which a table is stored. It is judged for each storage area that a file once backed up is not necessary to be backed up again. Data stored in the storage area and backed up as the collective backup or divisional backup is not backed up again. The backup time can therefore be shortened.

Abstract: Apparatus for identifying topics of document data has: a word ranker (171) for ranking words that are present in or representative of the content of the document data; a co-occurrence ranker (172) for ranking co-occurrences of words that are present in or representative of the content of the document data; a phrase ranker (170) for ranking phrases in the document data; a word selector (174) for selecting the highest ranking words; a co-occurrence identifier (176) for identifying which of the highest ranking co-occurrences contain at least one of the highest ranking words; a phrase identifier (177) for identifying the phrases containing at least one word from the identified co-occurrences; a phrase selector (178) for selecting the highest ranking one or ones of the identified phrases as the topic or topics of the document data; and an output device (40) for outputting data relating to the selected topics.

Abstract: The subject disclosure pertains to efficient computation of the difference between queries by exploiting commonality between them. A minimal difference query (MDQ) is generated that roughly corresponds to removal of as many joins as possible while still accurately representing the query difference. The minimal difference can be employed to further substantially the scope of view matching where a query is not wholly subsumed by a view. Additionally, the minimal difference query can be employed as an analytical tool in various contexts.

Abstract: A recovery method that uses log takes a long time to recover, and another recovery method that uses backup has the difficulties that if a computer abnormally stops its conversion process due to a failure, the result of the conversion performed up to the time of that abnormal stop couldn't be reflected on the later process for recovery. In a computer system, a system recovery management unit produces backup as the initial status of volume and snapshot taken when the system is operating, by use of a backup restore processing unit of a storage apparatus, and manages the situations of the process by use of a recovery point list/table. When a trouble occurs, it determines a point of recovery from the recovery point list/table, and makes the volume be recovered from the produced backup and the overwriting of meta data in order to keep the data consistency.