Abstract: A set of rules is formulated for what type of data may be missing from a record (in a sparse data database) and still be desirably included in a search result when a search engine having limited inputs is used. In other words, under what conditions may data in a non-specified (non-specifically searched) database field be used as a substitute for null values in a field directly corresponding to a field in a limited search value input box. These rules are then used by a search engine to generate a complex criteria statement which retrieves not only the records directly corresponding to the search request values input by a user, but also those additional records which logically may comply if all the data fields were filled.