Patent ID: 6564212
Filing Date: 2003-05-13
Classification: G06F,Y10S

Abstract:
A method of processing a query in a database system, wherein a plurality of row identifiers are defined to designate respective rows of a reference table having columns respectively associated with data attributes, said rows containing groups of related words assigned to said attributes in a collection of data, wherein a plurality of thesauruses each associated with a respective attribute and data representing reference table row identifier lists respectively associated with entries of said thesauruses are stored, wherein each thesaurus associated with one attribute is defined with reference to a partition into subsets of a set of words which can be assigned to said one attribute and has a respective entry for each subset including at least one word assigned to said one attribute in the collection of data, the reference table row identifier list associated with said thesaurus entry including any identifier allocated to a row of the reference table having a word of said subset assigned to said one attribute, the method comprising the steps of:determining a matching reference table row identifier list based on a combination of thesaurus entries relevant to the query and on the stored data representing the reference table row identifier lists associated with said relevant thesaurus entries; and processing said matching row identifier list to output a response, wherein the step of processing the matching row identifier list comprises, for at least one attribute specified in the query, selecting a thesaurus associated with said attribute and detecting entries of the selected thesaurus with which identifier lists having a non-empty intersection with the matching row identifier list are associated.