Self-referencing constraints

A self-referencing constraint exists if a Db2® object is subject to a primary or foreign key relationship in which the parent table and the dependent table are the same table. If the DELETE rule for the relationship is CASCADE, the deletion or change of one row can cause a recursive deletion of other rows in the table. If FM/Db2 detects a self-referencing constraint defined on a table, it does not attempt to determine which rows are affected by a deletion or change of a primary key value. This also applies to any other tables affected by other relationships defined on the table.