$UpdOval

The $UPDOVAL function is used in conjunction with the ON FIELD CONSTRAINT CONFLICT unit.

If $UPDOVAL is invoked from an ON FCC unit following the detection of an AT-MOST-ONE field-level constraint conflict, it returns the value of the original field occurrence which is causing the constraint violation. At all other times, $UPDOVAL returns a null string. The $UPDOVAL function takes no arguments.