Cursor with a variable as a parameter Oracle - database

Question

I have a function with a cursor. Within this cursor I want to get another cursor which I pass a parameter . This parameter is a value of the primary cursor. The logic that I have is like this:
CURSOR cursor1 IS
SELECT * FROM SCHEMAP.TABLA1 ;
registro cursor1%ROWTYPE;
CURSOR cursor2 (parametro IN NUMBER) IS
SELECT * FROM SCHEMAP.TABLA2 WHERE CAMPO_1 = parametro;
registroVac cursor2%ROWTYPE;
..........
BEGIN
.......
OPEN cursor1;
FETCH cursor1 INTO registro;
WHILE cursor1%found
LOOP
dbms_output.put_line('VARIABLE1:' + registro.VARIABLE1 );
OPEN cursor2(registro.VARIABLE1);
FETCH cursor2 INTO registroVac;
WHILE cursor2%found
LOOP
SELECT HC3PKDMUTILITIES.GET_DIAGNOSTIC_CODE_VAC(registro.VARIABLE1,registroVac.VAC_DOS,registroVac.VAC_CVH)
into v_diagnostic_code
from DUAL;
dbms_output.put_line('v_diagnostic_code -->' || v_diagnostic_code);
FETCH cursor2 INTO registroVac;
END LOOP;
CLOSE cursor2;
FETCH cursor1 INTO registro;
END LOOP;
CLOSE cursor1;
When I run the process I have an error in cursor2 like this:
ORA-06502: PL/SQL: numeric or value error: character to number conversion error CAMPO_1:102435313
CAMPO_1 is proven to be a numerical Database and registro.VARIABLE1 too. How to solve this problem?. Thanks.

Answer 1

Is this only a code-snipped and do you have more code in your application?
If not, then you can do it all in one which should be much faster and shorter:
CURSOR All_in_one IS
SELECT VARIABLE1,
HC3PKDMUTILITIES.GET_DIAGNOSTIC_CODE_VAC(registro.VARIABLE1,registroVac.VAC_DOS,registroVac.VAC_CVH) AS v_diagnostic_code
FROM SCHEMAP.TABLA2 t registroVac
RIGHT OUTER JOIN SCHEMAP.TABLA1 registro ON CAMPO_1 = VARIABLE1;

Answer 2

There are loads of things wrong with your code.
The thing that strikes me first is that you're opening cursor1, opening, fetching and closing cursor2, and then fetching from cursor1. That seems incorrect!
Secondly, why bother having two cursors and reinventing nested loop joins yourself? SQL is perfectly capable of handling joins, and the optimizer is pretty good at deciding which join to use (hash join, nested loops, etc).
Thirdly, if HC3PKDMUTILITIES.GET_DIAGNOSTIC_CODE_VAC is a function, why are you selecting it from dual (and therefore introducting context switching between the PL/SQL and SQL engines), rather than simply assigning the variable with the return value of the function?
I think you could rewrite the above code as simply:
declare
v_diagnostic_code varchar2(100); -- wasn't sure of the correct datatype; this is just a guess
begin
for rec in (select t1.variable1,
t2.vac_dos,
t2.vac_cvh
from schemap.tabla1 t1
inner join schemap.tabla2 t2 on (t2.campo_1 = t1.variable1))
loop
v_diagnostic_code := hc3pkdmutilities.get_diagnostic_code_vac(rec.variable1,rec.vac_dos,rec.vac_cvh);
dbms_output.put_line('variable1 --> '||rec.variable1||', v_diagnostic_code -->' || v_diagnostic_code);
end loop;
end;
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