ERROR : PLS-00103: Encountered the symbol ";" when expecting one of the following: * & = - + < / > at in is mod remainder not rem then

Question

This is a proyect for the University and I need some help :( What's the problem??

CREATE TABLE RESERVAS(
    OID_RE NUMBER NOT NULL,
    PrecioReserva INTEGER NOT NULL,
    fecha DATE NOT NULL,
    HoraInicio DATE NOT NULL,
    HoraFin DATE NOT NULL,
    OID_ESC NUMBER,
    OID_SOC NUMBER,
    OID_PIS NUMBER NOT NULL
);

CREATE OR REPLACE TRIGGER HorarioReseva
BEFORE INSERT OR UPDATE ON RESERVAS
FOR EACH ROW
DECLARE
    minutos NUMBER;
BEGIN 
    minutos := :NEW.HoraFin - :NEW.HoraInicio;
    IF(minutos > 120);
        THEN  raise_application_error
        ('No se puede reservar una pista durante más de 2h(120min)');
     END IF;
END;

Answer 1

Problems with your code:

• there is a semi-colon at the end of this expression, which should not be there IF(minutos > 120); (note that the parentheses are superfluous, as commented by William Robertson)

• raise_application_error() expects two arguments: an error number (between -20999 and -20000) and a message

• substrating DATEs produces a number that represents their difference in days; as it is, your code ensures that the difference is less than 120 days, which, as far as concerned, is not what you want.

Here is a correct version of your code:

CREATE OR REPLACE TRIGGER HorarioReseva
BEFORE INSERT OR UPDATE ON RESERVAS
FOR EACH ROW
DECLARE
    minutos NUMBER;
BEGIN 
    minutos := :NEW.HoraFin - :NEW.HoraInicio;
    IF minutos > 2/24
        THEN  raise_application_error(
            -20000,
            'No se puede reservar una pista durante más de 2h(120min)'
        );
     END IF;
END;
/

---

But basically: you want to ensure that the difference between HoraFin and HoraInicio is not greater than 2 hours. You don't need a trigger for this: a CHECK constraint is enough.

CREATE TABLE RESERVAS (
    OID_RE NUMBER NOT NULL,
    PrecioReserva INTEGER NOT NULL,
    fecha DATE NOT NULL,
    HoraInicio DATE NOT NULL,
    HoraFin DATE NOT NULL,
    OID_ESC NUMBER,
    OID_SOC NUMBER,
    OID_PIS NUMBER NOT NULL,
    CHECK(HoraFin - HoraInicio <= 2/24)
);

Demo on DB Fiddle:

insert into reservas (OID_RE, PrecioReserva, fecha, HoraInicio, HoraFin, OID_PIS)
values(
    1, 
    2, 
    to_date('2019-01-01', 'yyyy-mm-dd'), 
    to_date('2019-01-01 00:00:00', 'yyyy-mm-dd hh24:mi:ss'), 
    to_date('2019-01-01 02:00:00', 'yyyy-mm-dd hh24:mi:ss'),
    1
);
--> 1 rows affected

insert into reservas (OID_RE, PrecioReserva, fecha, HoraInicio, HoraFin, OID_PIS)
values(
    1, 
    2, 
    to_date('2019-01-01', 'yyyy-mm-dd'), 
    to_date('2019-01-01 00:00:00', 'yyyy-mm-dd hh24:mi:ss'), 
    to_date('2019-01-01 02:01:00', 'yyyy-mm-dd hh24:mi:ss'),
    1
);
--> ORA-02290: check constraint (FIDDLE_LTVQMOQEMVHALMINECEI.SYS_C00308788) violated