Setting up a stored procedure in Oracle - sql

Question

I'm working to create a stored procedure that takes input of an id and a start and end date, then returns trips that fall within that range. I've been looking over the oracle documentation and I think I'm close, but getting a few errors yet:
CREATE or replace PROCEDURE chg_per_aircraft
(p_aircraft_id IN RCC_AIRCRAFT.aircraft_id,
p_start_date IN date,
p_end_date IN date,
p_ttl_chg_per_acft OUT INTEGER)
AS
BEGIN
SELECT RCC_AIRCRAFT.aircraft_id,
SUM(RCC_CHARTER.distance * RCC_MODEL.charge_per_mile) ttl_chg
INTO
p_aircraft_id,
p_ttl_chg_per_acft
FROM RCC_AIRCRAFT
full join RCC_CHARTER
on RCC_CHARTER.aircraft_id = RCC_AIRCRAFT.aircraft_id
left join RCC_MODEL
on RCC_MODEL.model_code = RCC_AIRCRAFT.model_code
Where RCC_CHARTER.trip_date > p_start_date and RCC_CHARTER.trip_date < p_end_date
group by RCC_AIRCRAFT.aircraft_id;
SYS.DBMS_OUTPUT.PUT_LINE(ttl_chg);
end;

Answer 1

Your first error is the parameter definition:
p_aircraft_id IN RCC_AIRCRAFT.aircraft_id
should be
p_aircraft_id IN RCC_AIRCRAFT.aircraft_id%TYPE
But then you're selecting INTO p_aircraft_id, which is declared as an IN parameter, so you can't set it to a new value. Is that a variable you want to pass in, or a value you want to get out? It makes more sense as something the caller supplies along with the dates, but then you'd need to use it as a filter in the select statement. If there was more than one aircraft ID - likely if it's only restricted by date - then you'd get multiple results back, which would be a too_many_rows error anyway.
Your output will only be visible to a session that is set up to handle it, so that would perhaps make more sense for the caller to do; but in any case should be:
DBMS_OUTPUT.PUT_LINE(p_ttl_chg_per_acft);
... as ttl_chg only exists as a column alias, not a PL/SQL variable.
If you are passing in the aircraft ID, you might want something like this:
CREATE or replace PROCEDURE chg_per_aircraft
(p_aircraft_id IN RCC_AIRCRAFT.aircraft_id%TYPE,
p_start_date IN date,
p_end_date IN date,
p_ttl_chg_per_acft OUT INTEGER)
AS
BEGIN
SELECT SUM(RCC_CHARTER.distance * RCC_MODEL.charge_per_mile) ttl_chg
INTO p_ttl_chg_per_acft
FROM RCC_AIRCRAFT
JOIN RCC_CHARTER
ON RCC_CHARTER.aircraft_id = RCC_AIRCRAFT.aircraft_id
JOIN RCC_MODEL
ON RCC_MODEL.model_code = RCC_AIRCRAFT.model_code
WHERE RCC_CHARTER.trip_date > p_start_date
AND RCC_CHARTER.trip_date < p_end_date
AND RCC_AIRCRAFT.aircraft_id = p_aircraft_id
GROUP BY RCC_AIRCRAFT.aircraft_id;
-- just to debug!
DBMS_OUTPUT.PUT_LINE(p_ttl_chg_per_acft);
END;
/
I've also changed to inner joins as it doesn't seem useful to make them outer joins. This would also make more sense as a function than a procedure; though wrapping a single query in a stored program may be unnecessary anyway - though this looks like an assignment.