Partial-match queries and file designs
Walter A. Burkhard · 1975
Tnis paper is concernd with information retrieval based upon secondary keys; that is, keys which cannot in general uniquely identify a record, but can indicate certain attributes of the associated record. Partial-match retrieval deals with accessing and reading those records of a data base which match the user's query albeit the query is only partially specified. For example, suppose that 'the data base consists of the binary words 1010, 1110, 0011, 1101, 0010, 1111. The response to query 1**0 where * is a don't know symbol is the set of records with keys 1010 or 1110 while the response to query 1101 is the set of records with key 1101.