Introduction To Oracle9i: Advanced SQL Page 202 Deferred Enforcement Constraints may be defined with the deferrable option. This option will defer all constraint enforcement checking to the transaction level. The default is enforcement at the statement level. Example SQL> ALTER TABLE department ADD CONSTRAINT dpk PRIMARY KEY (dnumber) DEFERRABLE INITIALLY IMMEDIATE; Table altered. Why Defer Enforcement? The benefits of deferred enforcement may be explained with these comments: · Reduced complexity within application logic.