1. A computer implemented method for identifying one or more part numbers in a database of part numbers stored in a digital memory comprising: parsing each stored part number into one or more primary components and secondary components based on a first predetermined set of rules; calculating a relevance score for each component of each said stored part number; storing said relevance scores in said digital memory; receiving a query part number and parsing it into one or more query primary components and query secondary components based on a second predetermined set of rules; calculating a relevance score for each query component of said query part number; identifying each stored part number that has at least one component that matches a query component of said query part number; calculating for each identified stored part number: a) a first sum equal to the sum of the relevance scores of the one or more query components of the query part number that match a component of the identified stored part number; and b) a second sum equal to the sum of the relevance scores of the one or more components of the identified stored part number that match a query component; sorting the identified stored part numbers in a predetermined numerical order as a function of said first sum; and sorting the identified stored part numbers in a predetermined numerical order as a function of said second sum for any identified stored part numbers whose first sums are the same.