PROCEDURE CHECK_NULL(ITEM CHAR) IS
ERROR_ITEM VARCHAR2(50);
CURRENT_ITEM_LABEL VARCHAR2(100);
BEGIN
IF ERROR_TYPE='FRM' AND ERROR_CODE='40202' THEN
ERROR_ITEM:=:SYSTEM.TRIGGER_ITEM;
CURRENT_ITEM_LABEL:=GET_ITEM_PROPERTY(ERROR_ITEM,PROMPT_TEXT);
MESSAGE(CURRENT_ITEM_LABEL||' '||'cannot be empty');
RAISE FORM_TRIGGER_FAILURE;
ELSE
MESSAGE(ERROR_TEXT);
END IF; 
END;

CHECK_NULL(:PVIR.PVIR_N_REQUESTER);