Method and apparatus for maintaining referential integrity within a relational database in a data processing system

摘要

The invention relates to a method for determining the validity of a new referential constraint brought about by the creation or alteration of a selected data table within a relational data base, in a data processing system, having a plurality of related data tables. According to the invention the method is characterised by the steps of identifying which of the plurality of related data tables will be affected by the existence of the new referential constraint, and verifying the validity of the new referential constraint only upon the identified related data tables. The invention also relates to apparatus for determining the validity of a new referential constraint brought about by the creation or alteration of a selected data table within a relational database (14), in a data processing system (8), having a plurality of related data tables. According to the invention the apparatus comprises means (14, 18) for identifying which of the plurality of related data tables will be affected by the existence of the new referential constraint, and means for verifying the validity of the new referential constraint only upon the identified related tables.