Abstract: Techniques for using arbitrary sets of objects to constrain objects in database systems. The constraint set of objects is associated with the constrained object in the database system and the database system will perform an operation which adds an object to the constrained object only if the object being added belongs to the constraint set. In a preferred embodiment, the techniques are employed to obtain constraint sets of terms from ontologies which are then used to constrain columns containing those terms. An implementation of the techniques makes a materialized view out of the objects in the constraint set and uses the materialized view to define a referential integrity constraint on the constrained column.

Abstract: A database management system that has bitmap values in which set bits in a representation of a bitstring specify a set of objects whose definitions are built into the database management system. The database management system further includes user-accessible operations on the bitmap values. The bitmap values are represented by means of a mapping specifier that specifies a range of the set of objects and a representation of a string of bits that has been mapped onto the set of object specified by the range specifier. Objects containing bitmap values may be indexed by means of an index tree that includes summary bitmap values.

Abstract: A method for managing expressions includes receiving a first query that includes a first conditional expression. The first expression is then represented as data in a column of a table. A second query is received that specifies a first set of criteria, and the second query is executed to select data based at least on whether expressions in the column satisfy the first set of criteria. In an embodiment, the second query further specifies a second set of criteria, wherein executing the second query includes selecting data based on whether data in columns other than the expression column satisfy the second criteria. A special index is defined, which can be created on the column that stores the expressions as data, to filter large sets of expressions efficiently. A method of evaluating an expression set stored as data in a table classifies each predicate from each expression, and filters the expression set based on the predicate classification.

Abstract: The TABLE function mechanism available in a RDBMS is used to integrate RDF models into SQL queries. The table function invocation takes parameters including an RDF pattern, an RDF model, and an RDF rule base and returns result rows to the SQL query that contain RDF triples resulting from the application of the pattern to the triples of the model and the triples inferred by applying the rule base to the model. The RDBMS includes relational representations of the triples and the rules. Optimizations include indexes and materialized views of the representations of the triples, precomputed inferred triples, and a method associated with the TABLE function that rewrites the part of the SQL query that contains the TABLE function invocation as an equivalent SQL string. The latter technique is generally applicable to TABLE functions.

Abstract: The TABLE function mechanism available in a RDBMS is used to integrate RDF models into SQL queries. The table function invocation takes parameters including an RDF pattern, an RDF model, and an RDF rule base and returns result rows to the SQL query that contain RDF triples resulting from the application of the pattern to the triples of the model and the triples inferred by applying the rule base to the model. The RDBMS includes relational representations of the triples and the rules. Optimizations include indexes and materialized views of the representations of the triples, precomputed inferred triples, and a method associated with the TABLE function that rewrites the part of the SQL query that contains the TABLE function invocation as an equivalent SQL string. The latter technique is generally applicable to TABLE functions.

Abstract: A method for maintaining a system for database management. The method includes recording the addresses of newly created leaf blocks during a split operation on a primary B+tree and maintaining the new addresses in a list as part of primary B+tree metadata.

Abstract: A method for rapidly identifying terms that are associated with a given root term by a transitive relationship defined by hierarchical ontology data stored in a relational database. A transitive closure table is created that comprises a plurality of rows each of which specifies a term and an associated one of a plurality of root terms. The table is sorted and indexed by the root terms to group together rows associated with each of said root terms. The resulting transitive closure table may be consulted to rapidly identify terms associated with said given root term.

Abstract: The method for processing data in a relational database wherein ontology data that specifies terms and relationships between pairs of said terms expressed in an OWL document is stored in the database, database queries that include a semantic matching operator are formed which identify the ontology data and further specify a stated relationship between two input terms, and the query is executed to invoke the semantic matching operator to determine if the two input terms are related by the stated relationship by consulting said ontology data.

Abstract: A method is provided for determining and controlling feed water level in a steam generator of a nuclear power plant, whereby the water level sensor is calibrated in terms of the pressure drop across structural components in the feed water path. The water level differential pressure sensor is calibrated so that maximum water level is indicated as the level corresponding to the upper tap level plus the pressure drop across the foregoing structural components at maximum power plant power.

Abstract: A database management system that has bitmap values in which set bits in a representation of a bitstring specify a set of objects whose definitions are built into the database management system. The database management system further includes user-accessible operations on the bitmap values. The bitmap values are represented by means of a mapping specifier that specifies a range of the set of objects and a representation of a string of bits that has been mapped onto the set of object specified by the range specifier. The representation of the string of bits may be compressed. Bitmap operations on the values may alter the range specifier, the size of the string of bits, or individual bits in the string of bits. The objects represented by the bitmap values may be objects in the database management system or objects external thereto. An example of bitmap values of the first kind are bitmap values representing sets of rowids.

Abstract: A domain index for a partitioned database can be created using a user-defined indexing scheme. Partition maintenance operations performed on the partitioned database objects cause corresponding partition maintenance operations to be performed on the domain indexes. The user-supplied partitioning code is partition operation-unaware.

Abstract: Domain indexes (indexes created and maintained by user-defined indexing schemes) are managed on partitioned database objects that store data using a system-managed approach. Partition maintenance operations performed on the partitioned database objects cause corresponding partition maintenance operations to be performed on the domain indexes. Partition maintenance operations are performed on both the database objects and the indexes by a system-supplied partition manager. Changes in the partition maintenance operations or partitioning methods supplied by the database management system do not affect user-supplied code which is provided by the user-defined indexing scheme. User-supplied code is therefore partition operation-unaware.

Abstract: A mapping mechanism for a primary B+tree in a database management system. The primary B+tree includes a plurality of rows. The mapping mechanism includes introducing a mapping table that includes a plurality of rows, including a row for each row of the primary B+tree, and that stores the logical identifier of the corresponding primary B+tree row. In addition, reverse mapping is provided by augmenting a primary B+tree to include in each primary B+tree row a physical row identifier of the corresponding mapping table row. An auxiliary structure created on a primary B+tree can make use of the proposed mapping mechanism. Specifically, the auxiliary structures refers to primary B+tree rows indirectly by storing the physical row identifier of the corresponding mapping table row.

Abstract: A method for building bitmap indexes on a primary B+tree used for storing data in the database that has a mapping table associated with it. The bitmap index is built by using the mapping table row identifiers.

Abstract: A method and mechanism to execute a query against a partitioned database object. Data processed or created for an earlier partition is maintained even after further processing is performed against a subsequent partition. A shared data object, such as a context object, is maintained to store data from processing the partitions of a partitioned table. Rather than discarding or overwriting the shared data object after processing each partition, the data from a subsequent partition is instead appended to the shared data object.

Abstract: A system for organizing and accessing a database. The system includes a primary B+tree index, a secondary B+tree index, a plurality of mapping table row identifiers stored in the secondary B+tree index and a plurality of database addresses for leaf blocks of the primary B+tree index corresponding to mapping table rows.

Abstract: A method and system for optimizing the execution of database statement is described. Optimization of database statements having non-boolean predicates is disclosed. Also disclosed is the determination and use of different granularity levels of information for submitting database statement predicates to optimizer-related functions.

Abstract: A system for organizing and accessing a database. The system includes a primary B+tree index, a secondary B+tree index, a plurality of mapping table row identifiers stored in the secondary B+tree index and a plurality of database addresses for leaf blocks of the primary B+tree index corresponding to mapping table rows.

Abstract: A method for managing expressions includes receiving a first query that includes a first conditional expression. The first expression is then represented as data in a column of a table. A second query is received that specifies a first set of criteria, and the second query is executed to select data based at least on whether expressions in the column satisfy the first set of criteria. In an embodiment, the second query further specifies a second set of criteria, wherein executing the second query includes selecting data based on whether data in columns other than the expression column satisfy the second criteria. A special index is defined, which can be created on the column that stores the expressions as data, to filter large sets of expressions efficiently. A method of evaluating an expression set stored as data in a table classifies each predicate from each expression, and filters the expression set based on the predicate classification.

Abstract: A database system having logical row identifiers (rowids) includes a secondary index which is traversed to locate a secondary index entry that includes a target secondary key value. Each secondary index entry also includes a logical rowid element. Each logical rowid element has both a primary key value element, and a datablock address element identifying a leaf block in an index-organized table that likely includes a row corresponding to the primary key value element. The leaf block is scanned to locate the row in the index-organized table that includes the target secondary key value and corresponds with the located, secondary index entry. A primary key scan is performed on the index-organized table if the row in the index-organized table is not located in the identified datablock.