11. Trigeri
/*triger koji upisuje današnji datum ako se izostavi pri upisu ocene albuma*/
CREATE OR REPLACE TRIGGER trig1
before INSERT OR UPDATE ON album
FOR each ROW
BEGIN
IF (:NEW.ocena1 IS NOT NULL AND :NEW.dat_ocena1 IS NULL)THEN
:NEW.dat_ocena1 := CURRENT_DATE;
END IF;
IF (:NEW.ocena2 IS NOT NULL AND :NEW.dat_ocena2 IS NULL) THEN
:NEW.dat_ocena2 := CURRENT_DATE;
END IF;
END;

INSERT INTO Album(ID_ALB, NAZIV, DAT_POC, ID_ZAP, OCENA2)
VALUES(190,'The Wall',TO_DATE('11-JUN-2000','DD-MON-YYYY'), 1, 5);

/*triger koji na promenu producenta dodaje vrednost u pesma_istorija

create or replace trigger trig2
before update of id_zap on pesma
for each row
declare

redniBroj number;
datumPocetka pesma.dat_poc%type;
danas date;
begin

select to_date(SYSDATE)
into danas
from DUAL;

select nvl(min(rbr_pi), 1)
into redniBroj
from pesma_istorija
where id_pesma = :old.id_pesma;

select dat_poc
into datumPocetka
from pesma
where id_zap = :new.id_zap;

insert into pesma_istorija values
(redniBroj, datumPocetka, danas, :old.id_pesma, :old.id_zap);
end;