Patent ID: 8117231

Claim:
A computer implemented method of constructing category structures within a database, the method including: using one or more processors, providing in the database a first structure of categories as a first hierarchy of categories to provide a classification of a data item, the providing of the first structure of categories including defining the first hierarchy of categories; using the one or more processors, providing in the database a second structure of categories as an alternative second hierarchy of categories to provide an alternative classification of the data item, the providing of the second structure of categories including defining the second hierarchy of categories such that navigation of the second hierarchy of categories to locate the data item classified in a second category of the second hierarchy of categories identifies the data item as being classified in a first category of the first hierarchy of categories, the defining of the first and second hierarchies of categories includes defining a category table, the category table including a category record for the first category and a category record for the second category, the category record for the second category further including a category identifier for the category record for the first category.