Abstract: A method, information processing system, and computer program storage product to compress sorted values. At least a first prefix and a second prefix in a plurality of prefixes are compared. Each prefix comprises at least a portion of a plurality of sorted values. A respective prefix comprises a set of consecutive characters including at least a first character of a respective sorted value. The respective sorted value further comprising a respective suffix comprising consecutive characters of the respective sorted value that are after the respective prefix. At least a respective first character of the first prefix and a respective first character of the second prefix are determined to be substantially identical. The first prefix is merged with the second prefix into a single prefix comprising the first character. A set of suffixes associated with the first prefix is updated to reflect an association with the second prefix.

Abstract: A system and method for managing a cache includes monitoring a temperature of regions on a secondary storage based on a cumulative cost to access pages from each region of the secondary storage. Similar temperature pages are grouped in logical blocks. Data is written to a cache in a logical block granularity by overwriting cooler blocks with hotter blocks.

Abstract: A system and method for managing a cache includes monitoring a temperature of regions on a secondary storage based on a cumulative cost to access pages from each region of the secondary storage. Similar temperature pages are grouped in logical blocks. Data is written to a cache in a logical block granularity by overwriting cooler blocks with hotter blocks.

Abstract: A method, information processing system, and computer readable storage product estimate a compression factor. A set of key values within an index are analyzed. Each key value is associated with a record identifier (“RID”) list comprising a set of RIDs. The index is in an uncompressed format and includes a total byte length. A number of RIDs associated with each key value is estimated for each key value in the set of key values. A total byte length for all RID deltas between each at least two consecutive RIDs within a RID list is estimated for each RID list based on the number of RIDs that have been determined. The total byte length estimated for each RID list is accumulated. A compression factor associated with the index is determined by dividing the total byte length that has been accumulated by the byte length of the index.

Abstract: Disclosed is a method, information processing system, and computer readable medium for preserving privacy of nonstationary data streams. The method includes receiving at least one nonstationary data stream with time dependent data. Calculating, for a given instant of sub-space of time, A set of first-moment statistical values is calculated, for a given instant of sub-space of time, for the data. The first moment statistical values include a principal component for the sub-space of time. The data is perturbed with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the data is perturbed by the noise only within a predetermined variance.

Abstract: A method, information processing system, and computer readable medium are provided for preserving privacy of one-dimensional nonstationary data streams. The method includes receiving a one-dimensional nonstationary data stream. A set of first-moment statistical values are calculated, for a given instant of sub-space of time, for the data. The first moment statistical values include a principal component for the sub-space of time. The data is perturbed with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the data is perturbed by the noise only within a predetermined variance.

Abstract: A method, information processing system, and computer program storage product for compressing sorted values is disclosed. At least a first prefix and a second prefix in a plurality of prefixes are compared. Each prefix comprises at least a portion of a plurality of sorted values. A respective prefix comprises a set of consecutive characters including at least a first character of a respective sorted value. The respective sorted value further comprising a respective suffix comprising consecutive characters of the respective sorted value that are after the respective prefix. At least a respective first character of the first prefix and a respective first character of the second prefix are determined to be substantially identical. The first prefix is merged with the second prefix into a single prefix comprising the first character. A set of suffixes associated with the first prefix is updated to reflect an association with the second prefix.

Abstract: A method, information processing system, and computer readable storage product estimate a compression factor. A set of key values within an index are analyzed. Each key value is associated with a record identifier (“RID”) list comprising a set of RIDs. The index is in an uncompressed format and includes a total byte length. A number of RIDs associated with each key value is estimated for each key value in the set of key values. A total byte length for all RID deltas between each at least two consecutive RIDs within a RID list is estimated for each RID list based on the number of RIDs that have been determined. The total byte length estimated for each RID list is accumulated. A compression factor associated with the index is determined by dividing the total byte length that has been accumulated by the byte length of the index.

Abstract: A method, information processing system, and computer readable medium are provided for preserving privacy of one-dimensional nonstationary data streams. The method includes receiving a one-dimensional nonstationary data stream. A set of first-moment statistical values are calculated, for a given instant of sub-space of time, for the data. The first moment statistical values include a principal component for the sub-space of time. The data is perturbed with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the data is perturbed by the noise only within a predetermined variance.

Abstract: Disclosed is a method, information processing system, and computer readable medium for preserving privacy of nonstationary data streams. The method includes receiving at least one nonstationary data stream with time dependent data. Calculating, for a given instant of sub-space of time, A set of first-moment statistical values is calculated, for a given instant of sub-space of time, for the data. The first moment statistical values include a principal component for the sub-space of time. The data is perturbed with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the data is perturbed by the noise only within a predetermined variance.

Abstract: A method for providing ontology management that leaves existing instance data stored in a relational database, while virtualizing the existing instance data for accesses originating from an ontology application, wherein the method includes: submitting an ontology application query to an ontology management system; rewriting the ontology application query with a mapping module into a vertical format mapped query; submitting the vertical format mapped query and view definitions to a database query processor; retrieving relevant existing instance data from the relational database in response to request from the database query processor; and virtualizing the retrieved relevant existing instance data for use by the ontology application.

Abstract: A system and method of converting a recursive XML document into a relational schema comprises providing a recursive XML document; parsing an external mapping script specifying a mapping from the recursive XML document to a relational table format; building a recursive shredding tree based on the external mapping script and the relational table format; and shredding the mapped recursive XML document into a relational table. The system and method further comprise detecting whether any of a XML schema and a DTD document is recursive, wherein the detecting comprises building a directed graph comprising element names; corresponding elements names as nodes in the directed graph; forming arcs from every element parent node to every element child node of the element parent node; and checking for cycles in the directed graph. The system and method further comprise identifying all recursive cursor nodes and a recursive degree corresponding to the recursive shredding tree.

Abstract: A computer-implemented method and system for determining search results for a search query for hypertext documents. The hypertext documents are reviewed to determine expert documents. When a query is received, the expert documents are ranked in accordance with the query. Then the target documents of the ranked expert documents are ranked to determine the search result set.

Abstract: A method, a system and recording medium for maintaining the order of nodes in a hierarchical document. The method may select the maximum and the minimum number of children for each node, build an auxiliary ordered tree having at least as many leaves as atoms within the hierarchical document based upon the selected maximum and minimum number of children for each node, attach the atoms to the leaves of the auxiliary ordered tree, and label each of the nodes in the auxiliary ordered tree.

Abstract: A system and method of converting a recursive XML document into a relational schema comprises providing a recursive XML document; parsing an external mapping script specifying a mapping from the recursive XML document to a relational table format; building a recursive shredding tree based on the external mapping script and the relational table format; and shredding the mapped recursive XML document into a relational table. The system and method further comprise detecting whether any of a XML schema and a DTD document is recursive, wherein the detecting comprises building a directed graph comprising element names; corresponding elements names as nodes in the directed graph; forming arcs from every element parent node to every element child node of the element parent node; and checking for cycles in the directed graph. The system and method further comprise identifying all recursive cursor nodes and a recursive degree corresponding to the recursive shredding tree.

Abstract: A tagging tree that defines a hierarchical output data structure and relational database query operations that retrieve the data to be included in each hierarchical section is accepted and processed. A query optimizer analyzes the tagging tree to determine database query operations that can be combined into a single query command. An outer-union query command is generated to allow efficient combination of multiple query commands, some of which are predicates to others. The tagging tree is modified to replace the database queries that were combined into the outer-union query to extract data from the results set produced by the outer-union query as opposed to submitting queries to the database manager. The optimized queries can be reused an arbitrary number of times to leverage the optimizing resources that were used in their creation.

Abstract: A method for determining relationships between hierarchically structured schema components and their effects on and content of tuples, includes: analyzing the hierarchically structured schema with user-supplied mappings and finding elements or attributes mapped to a same relational table; determining relationships between the elements or attributes to be either a one-to-one relationship or a one-to-many relationship based on an information set in the hierarchically structured schema; recording the relationships; and processing a hierarchically structured document against the recorded relationships and generating tuples accordingly. The constructs of a hierarchically structured schema that may affect the cardinality between the attributes of a relation, and thus the contents of the tuples, are considered. A relationship between the hierarchically structured schema model and a relational model is established.

Abstract: A method and system for preparing a relational database for searching includes determining a hierarchy of data within the relational database, and storing a hierarchical label for at least one record of data within the relational database that corresponds to the hierarchy of the data.

Abstract: A computer-implemented method is provided for performing key lookups. The method comprises accessing a header of a given one of a plurality of nodes in a tree-based data index structure. The given node comprises the header and a plurality of partitions. Each partition comprises at least one key. The header of the given node comprises a selected key from each of a selected plurality of the partitions. The method also comprises choosing, using a search key, a selected key in the header. The method further comprises accessing a partition corresponding to the chosen selected key and selecting, using the search key, one of the at least one keys in the accessed partition. The selected one of the at least one keys can be used to access another of the plurality of nodes. Yet additional methods, apparatus, and program products are disclosed.

Abstract: A method and system that allows efficient shredding of large instances of hierarchical data structures into relational data structures. Large instances of hierarchical data structures, which are able to be larger than the random access storage of a computer used to shred them into relational data structures, are incrementally shredded into a temporary storage. When the amount of data shredded into the temporary storage reaches or exceeds a predetermined commit count, the data in the temporary storage is transferred to a relational data structure maintained by a relational database manager. A Document Type Description annotation is provided to allow the end user to specify execution order for SQL commands and to specify commit count values.