(1) A field used to arrange the records of a particular type within a file member.
(2) In EJB query language, a container-managed field in an entity bean that corresponds to one of the primary-key columns of a row in a relational database. Each key field is a member of the entity bean's key class.
(3) The portion of a record that is used (possibly with other key fields) to locate a data record in a key file See also alternate key.
(4) The field in a database segment used to store segment occurrences in sequential ascending order. A key field is also a search field. See also search field.
(5) See sequence field.