69. The computer program product of claim 68, for performing an exact search, comprising: means for causing a computer to effect reducing the dimensionality of specified data, based on the dimensionality reduction information for the database; means for causing a computer to effect associating reduced dimensionality specified data to one of the clusters, based on the clustering information, in response to said reducing; means for causing a computer to effect reducing a dimensionality of reduced dimensionality specified data to that of a reduced dimensionality cluster defined by an associated cluster, based on dimensionality reduction information for the associated cluster; and means for causing a computer to effect searching for a matching reduced dimensionality cluster, based on a reduced dimensionality version the specified data.
68. The computer program product of claim 51, wherein the data is stored in a database, further comprising: means for causing a computer to effect reducing a dimensionality of the database and generating dimensionality reduction information associated with the database; and means for causing a computer to effect storing the dimensionality reduction information associated with the database; wherein said partitioning step is responsive to said reducing step.