Note. INSTEAD OF DELETE and INSTEAD OF UPDATE triggers cannot be defined on a table that has a foreign key that is defined by using a DELETE or UPDATE cascading action. Coding this logic as part of an INSTEAD OF trigger prevents all applications that access the data from having to reimplement the logic.Example.NSTEAD OF DELETE and INSTEAD OF UPDATE triggers cannot be defined on a table that has a foreign key that is defined by using a DELETE or UPDATE cascading action. Coding this logic as part of an INSTEAD OF trigger prevents all applications that access the data from having to reimplement the logic. Example.