公开(公告)号：AU629928B2

公开(公告)日：1992-10-15

申请号：AU5506590

申请日：1990-05-15

Applicant: IBM

Inventor： HALL GARY RANDALL ,  MALKEMUS TIMOTHY RAY

IPC: G06F17/30 ,  G06F20060101 ,  G06F12/00 ,  G06F15/40

Abstract: 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.