I have a problem with triggers i sql Oracle

Question

(zaposlenik means emplpoyee, godisnji_odmor means vacation) So I want to make a trigger that triggers if an employee(here is called zaposlenik) has more than 21 days of vacation after an insert in year 2020. An employee can have multiple vacations(like 2 days, 10 days...) one to many relation between tables zaposlenik(employee) and godisnji_odmor(vacation). My problem here is that I don't know how to get that zaposlenik_id from the insert on which the trigger tiggers so I can sum up the vacation days of that employee on the ID = zaposlenik_id.

Here are my tables and trigger.

CREATE TABLE zaposlenik  
(
    zaposlenik_id INTEGER CONSTRAINT zaposlenik_pk PRIMARY KEY,
    posao VARCHAR(30) NOT NULL,
    ime VARCHAR(30) NOT NULL,
    prezime VARCHAR(30) NOT NULL,
    broj_tel INTEGER NOT NULL,
    email VARCHAR(50) NOT NULL,
    adresa VARCHAR(100) NOT NULL,
    mjesecni_iznos_place FLOAT NOT NULL,
    IBAN VARCHAR(34) NOT NULL,
    budzet FLOAT,
    parking_mjesto_id VARCHAR(5) CONSTRAINT zaposlenik_parking_mjesto_fk REFERENCES
        parking_mjesto(etaza_i_br_mjesta),

    zaposlenik_id_2 INTEGER CONSTRAINT zaposlenik_zaposlenik_fk REFERENCES 
        zaposlenik(zaposlenik_id)
);

CREATE TABLE godisnji_odmor
(
    godisnji_odmor_id INTEGER CONSTRAINT godisnji_odmor_pk PRIMARY KEY,
    pocetak DATE NOT NULL,
    kraj DATE NOT NULL,
    zaposlenik_id INTEGER NOT NULL CONSTRAINT godisnji_odmor_zaposlenik_fk REFERENCES
        zaposlenik(zaposlenik_id)
);

CREATE OR REPLACE TRIGGER t_godisnji
    AFTER INSERT
    ON godisnji_odmor
DECLARE
    v_br NUMBER; --sum of the vacation days
    v_id NUMBER; -- id of the employee that is inserted (his id is zaposlenik_id)
BEGIN
    SELECT zaposlenik_id INTO v_id FROM INSERTED;

    SELECT SUM( g.kraj - g.pocetak ) INTO v_br 
    FROM zaposlenik z INNER JOIN godisnji_odmor g USING(zaposlenik_id)
    WHERE g.pocetak > '01-JANUARY-2020' AND zaposlenik_id = v_id;

    IF v_br > 21 THEN
        ROLLBACK;
        raise_application_error(-20100,'Godisnji prekoracuje 21 dan u sumi');
    END IF;
END t_godisnji;
/

Answer 1

You need to use the :new for this as follows:

replace

SELECT zaposlenik_id INTO v_id FROM INSERTED;

with

v_id := :new.zaposlenik_id; 

In short, You can have your code without v_id variable as follows:

CREATE OR REPLACE TRIGGER t_godisnji
    AFTER INSERT
    ON godisnji_odmor
DECLARE
    v_br NUMBER; --sum of the vacation days
    --v_id NUMBER; -- id of the employee that is inserted (his id is zaposlenik_id)
BEGIN
    --SELECT zaposlenik_id INTO v_id FROM INSERTED;

    SELECT SUM( g.kraj - g.pocetak ) INTO v_br 
    FROM zaposlenik z INNER JOIN godisnji_odmor g USING(zaposlenik_id)
    WHERE g.pocetak > '01-JANUARY-2020' 
      AND zaposlenik_id = :new.zaposlenik_id; -- see the usage of :new here

    IF v_br > 21 THEN
        ROLLBACK;
        raise_application_error(-20100,'Godisnji prekoracuje 21 dan u sumi');
    END IF;
END t_godisnji;
/