How can I test my package with one function? - oracle

I made a package that compiles fine but when I try to test it it gives me "invalid data type".
I've tried two different ways, first one like this
select pkg_contabilidad.f_totalizar_Detalle(100) FROM DUAL;
It gives me the ORA-00902 'invalid data type'
Also I've tried this
DECLARE
TYPE r_registro IS RECORD
(rubro_contable CN_RUBROS_CONTABLES.COD_RUBRO%TYPE,
tipo VARCHAR2(1),
monto NUMBER(16));
resultao r_registro;
numero NUMBER :=100;
BEGIN
resultao := pkg_contabilidad.f_totalizar_detalle(numero);
END;
It gives me another error PLS-00382 'expression is of wrong type'
I don't know what am I doing wrong, cause my function receives just one parameter and is of type NUMBER, so I dont know where's my mistake. I'll leave the code of my package just in case
CREATE OR REPLACE PACKAGE pkg_contabilidad AS
TYPE r_registro IS RECORD
(rubro_contable CN_RUBROS_CONTABLES.COD_RUBRO%TYPE,
tipo VARCHAR2(1),
monto NUMBER(16));
TYPE t_detalle IS TABLE OF
r_registro INDEX BY BINARY_INTEGER;
FUNCTION f_totalizar_detalle(p_clave NUMBER)RETURN t_detalle;
END pkg_contabilidad;
/
CREATE OR REPLACE PACKAGE BODY pkg_contabilidad AS
B_detalle t_detalle;
i integer :=1;
FUNCTION f_totalizar_detalle(p_clave NUMBER) RETURN t_detalle IS
v_detalle t_detalle;
CURSOR c_facturado IS
SELECT c.cod_rubro, 'H', CASE WHEN SUM(d.gravada)=0 THEN SUM(d.iva) ELSE SUM(d.gravada) END
FROM fn_documentos_det d JOIN fn_conceptos c ON d.cod_concepto = c.cod_concepto
WHERE d.clave_doc=p_clave
GROUP BY c.cod_rubro;
CURSOR c_datos IS
SELECT SUM(d.total_doc), 'D',r.cod_rubro
FROM fn_documentos d JOIN fn_cajas_ctas r ON d.num_caja_cta = r.num_caja_cta
WHERE d.clave_doc = p_clave
GROUP BY r.cod_rubro;
BEGIN
open c_datos;
LOOP
FETCH c_datos INTO v_detalle(1);
END LOOP;
CLOSE c_datos;
FOR fila IN c_facturado LOOP
i := i + 1;
v_detalle(i) := fila;
END LOOP;
END;
END PKG_CONTABILIDAD;

The function returns a pkg_contabilidad.t_detalle, so the test needs to be:
declare
resultao pkg_contabilidad.t_detalle;
numero number := 100;
begin
resultao := pkg_contabilidad.f_totalizar_detalle(numero);
end;
It doesn't work in SQL because pkg_contabilidad.t_detalle is a PL/SQL type, not a SQL type (create or replace type). The database can perform some automatic conversions, but there are still limitations.
By the way, this loop will never complete because it lacks an exit condition:
open c_datos;
loop
fetch c_datos into v_detalle(1);
end loop;
close c_datos;

Your function returns a PL/SQL table type, with a table of a PL/SQL record type, which is defined in your package, which plain SQL doesn't know about and can't display - hence your invalid datatype error. If you need to call the function and access the data from SQL you can create schema-level object and collection types instead.
In your anonymous block you are a declaring a new record type. That looks the same to you because the structure is the same, but Oracle expects the exact type the function returns. That makes your test code shorter and simpler though. But you are also trying to return the whole collection into a single record.
DECLARE
l_detalle pkg_contabilidad.t_detalle;
l_registro pkg_contabilidad.r_registro;
l_idx pls_integer;
numero NUMBER :=100;
BEGIN
l_detalle := pkg_contabilidad.f_totalizar_detalle(numero);
l_idx := l_detalle.FIRST;
WHILE l_idx is not null LOOP
l_registro := l_detalle(l_idx);
-- do something with this record
dbms_output.put_line(l_registro.tipo);
l_idx := l_detalle.NEXT(l_idx);
END LOOP;
END;
db<>fiddle with dummy cursors.
Your function is a bit strange and probably isn't doing quite what you want; but also has two fatal problems: it isn't returning anything, and it has an infinite loop. I've fixed those for the fiddle but not anything else, as this seems to be an exercise.

Related

VARCHAR2(32767) not able to handle strings in stored procedure

I am concatenating string using cursor (to form query to execute later). Here, the query that will be formed is going to be way bigger that what VARCHAR2(32767) can handle. There fore, I am getting error on proc execution - ORA-06502: PL/SQL: numeric or value error: character string buffer too small.
I used CLOB data type as well bu got error ORA-06502: PL/SQL: numeric or value error.
My code is here below:
CREATE OR REPLACE PROCEDURE sp_Market
IS
Names VARCHAR2(32767);
BEGIN
DECLARE CURSOR cur IS ('Select ID, Order_of, field_name
FROM pld_medicare_config');
BEGIN
FOR i IN cur
LOOP
Names := Names || i.sqql;
END LOOP;
dbms_output.put_line(Names);
END;
END sp_Market;
How can I handle my string of queries and what data type is there to accomplish the task?
CLOB is OK (as far as I can tell); I doubt queries you store in there are that big.
Remove dbms_output.put_line call from the procedure; I suspect it is the one that raises the error.
I'm not sure how you got any runtime error, as your procedure won't compile.
The valid PL/SQL version would look something like this:
create or replace procedure sp_market is
names varchar2(32767);
begin
for r in (
select id, order_of, field_name
from pld_medicare_config
)
loop
names := names || ' ' || r.field_name;
end loop;
names := ltrim(names);
dbms_output.put_line(names);
end sp_market;
If names needs to be longer, change the datatype to clob.
Use the CLOB datatype and append data using the dbms_lob.writeappend procedure. This is the reference (Oracle 18c).
The error probably origins with the dbms_output.put_line call. The procedure is defined for varchar2 arguments only which means that an implicit conversion takes place during the call. It will fail for clob contents longer than 32767 chars/bytes.
Alternatively you may declare a collection over varchar2(4000) and fill the collection elements sequentially:
CREATE OR REPLACE PROCEDURE sp_Market
IS
TYPE tLongString IS TABLE OF VARCHAR2(4000) INDEX BY BINARY_INTEGER;
cNames tLongString;
BEGIN
DECLARE CURSOR cur IS Select ID, Order_of, field_name, sqql FROM pld_medicare_config;
BEGIN
FOR i IN cur
LOOP
cNames(cNames.COUNT+1) := i.sqql;
END LOOP;
END;
END sp_Market;
Note
Rectified code, will compile now.

How to call list of package methods dynamically in PL/SQL

I have a scenario that I want to execute dynamically fetched methods from a cursor with different arguments. Those argument values are replaced (using Get_Parameter_Value___(head_rec_.objkey,parameter_); ) with values in a loop as you can see in the following example.
PROCEDURE Dynamic_exe(
keyvalue_ IN VARCHAR2)
IS
param_str_ VARCHAR2(2000);
temp_param_str_ VARCHAR2(2000);
method_stmt_ VARCHAR2(100);
CURSOR get_method IS
SELECT exe_method
FROM method_tab
BEGIN
param_str_ := Substr(rec_.exe_method,Instr(rec_.exe_method,'(')+1,(Instr(rec_.exe_method,')')-1)-Instr(rec_.exe_method,'('));
temp_param_str_ := param_str_;
method_stmt_ := rec_.exe_method;
WHILE temp_param_str_ IS NOT NULL LOOP
IF (Instr(temp_param_str_,',') > 0 )THEN
parameter_ := trim(Substr(temp_param_str_,1,Instr(temp_param_str_,',')-1));
temp_param_str_ := Substr(temp_param_str_,Instr(temp_param_str_,',')+1);
ELSE
parameter_ := trim(temp_param_str_);
temp_param_str_ := NULL;
END IF;
parameter_value_ := Get_Parameter_Value___(head_rec_.objkey,parameter_);
method_stmt_ := REPLACE(method_stmt_,parameter_,''''||parameter_value_||'''');
END LOOP;
FOR rec_ IN get_method LOOP
EXECUTE IMMEDIATE 'BEGIN '||method_stmt_||'; END;';
END LOOP;
END Dynamic_exe;
This is not safe, SQL injection can be done for this, I need a solution, associated with bind variables, Does anyone have a solution for this?
You can eliminate the possibility of SQL injection by using DBMS_ASSERT.SQL_OBJECT_NAME to protect the method name, and use DBMS_SQL and bind variables to protect the arguments.
DBMS_ASSERT.SQL_OBJECT_NAME throws an error if the value is not the same as an existing object. (Although for packages it only checks that the package name exists, not the procedure name. But the procedure name must still be a realistic name.)
For example, if the package name exists, the function will simply return the name:
SQL> select dbms_assert.SQL_OBJECT_NAME('test_package.test_procedure') name from dual;
NAME
--------------------------------------------------------------------------------
test_package.test_procedure
But any SQL injection shenanigans will raise an exception (which you can catch and handle if necessary):
SQL> select dbms_assert.sql_object_name('; delete from employees;') from dual;
select dbms_assert.sql_object_name('; delete from employees;') from dual
*
ERROR at line 1:
ORA-44002: invalid object name
ORA-06512: at "SYS.DBMS_ASSERT", line 401
Instead of building the entire statement as a string, add :bind_variable_n and DBMS_SQL to run it.
So the final string will look something like this (add the bind variable numbers in the loop):
method_stmt_ := 'begin '||method_name||'(:1, :2); end;';
Executing a dynamic number of bind variables requires DBMS_SQL.BIND_VARIABLE. Switching from native dynamic SQL to DBMS_SQL is going to be annoying, but it will let you pass in the bind variables without any injection concerns.

Oracle: How to populate/insert row to a Ref Cursor?

Really need help regarding Ref Cursor. I have a Stored Procedure GET_PERSONROLES that have parameter type ref cursor. I just wanted to pupulate this ref cursor manually like inserting a row to the refcursor.
Can I insert a row into a refcursor though a loop?
Thank you in advance.
The procedure depends on this publicly declared type:
create or replace package types
as
type cursorTypePersonRole is ref cursor;
end;
Here is my pseudo-codeL
create or replace PROCEDURE GET_PERSONROLES
(
P_CURSOR IN OUT types.cursorTypePersonRole
) AS
REFCUR SYS_REFCURSOR;
TYPE REFTABLETYPE IS RECORD (
IS_MANAGER_LEVEL1 VARCHAR2(1),
IS_MANAGER_LEVEL2 VARCHAR2(1)
);
TYPE TABLETYPE IS TABLE OF REFTABLETYPE;
PERSONROLES_TABLETYPE TABLETYPE;
BEGIN
--calls another stored proc to populate REFCUR with data without problem
MY_STOREDPROC('12345', REFCUR);
LOOP
FETCH REFCUR BULK COLLECT INTO PERSONROLES_TABLETYPE;
EXIT WHEN PERSONROLES_TABLETYPE.COUNT = 0;
FOR indx IN 1 .. PERSONROLES_TABLETYPE.COUNT
LOOP
-- I'm able to query perfectly the values of IS_MANAGER_LEVEL1 and IS_MANAGER_LEVEL 2
-- I'm aware that the below codes are wrong
-- However this means I wanted to insert these values to a row of the cursor if possible
-- Do some logic to know what data will be assigned in the row.
if PERSONROLES_TABLETYPE(indx).IS_MANAGER_LEVEL1 = 'Y' then
P_CURSOR := <DO SOME LOGIC AND ASSIGN THE VALUE TO THE ROW>
end if;
if PERSONROLES_TABLETYPE(indx).IS_MANAGER_LEVEL2 = 'Y' then
P_CURSOR := <DO SOME LOGIC AND ASSIGN THE VALUE TO THE ROW>
end if;
END LOOP;
END LOOP;
CLOSE REFCUR;
END GET_PERSONROLES;
A ref cursor is not a variable: it is a pointer to a result set which is consumed by the act of reading it. The result set itself is immutable.
Immutability makes sense, because it reflects Oracle's emphasis on read consistency.
The simplest way to produce the output you appear to want is to create a SQL Type
open P_CURSOR for
select IS_MANAGER_LEVEL1,
IS_MANAGER_LEVEL2
from table ( PERSONROLES_TABLETYPE );
This will work in 12c; in earlier versions to use the table() call like this you may need to declare REFTABLETYPE and TABLETYPE as SQL types( rather than in PL/SQL).
"Ok edited it now"
Alas your requirements are still not clear. You haven't given us the structure of the output ref cursor or shown what other processing you want to undertake.
However, given the title of your question, let's have a guess. So:
create or replace PROCEDURE GET_PERSONROLES ( P_CURSOR IN OUT types.cursorTypePersonRole) AS
REFCUR SYS_REFCURSOR;
TYPE REFTABLETYPE IS RECORD (IS_MANAGER_LEVEL1 VARCHAR2(1),
IS_MANAGER_LEVEL2 VARCHAR2(1));
TYPE TABLETYPE IS TABLE OF REFTABLETYPE;
PERSONROLES_TABLETYPE TABLETYPE;
personrole_rec PersonRole%rowtype;
type personrole_nt is table of PersonRole%rowtype;
personroles_recs personrole_nt := new personrole_nt() ;
BEGIN
MY_STOREDPROC('12345', REFCUR);
FETCH REFCUR BULK COLLECT INTO PERSONROLES_TABLETYPE;
FOR indx IN 1 .. PERSONROLES_TABLETYPE.COUNT LOOP
/* in the absence of requirements I'm just making some stuff up */
if PERSONROLES_TABLETYPE(indx).IS_MANAGER_LEVEL1 = 'Y' then
personrole_rec.whatever1 := 'something';
else
personrole_recc.whatever1 := null;
end if;
if PERSONROLES_TABLETYPE(indx).IS_MANAGER_LEVEL2 = 'Y' then
personrole_rec.whatever2 := 'something else';
else
personrole_recc.whatever2 := null;
end if;
if personrole_rec.whatever1 is not null
or personrole_rec.whatever2 is mot null then
personroles_recs.exend();
personroles_recs(personroles_recs.count()) := personroles_rec;
end if;
END LOOP;
CLOSE REFCUR;
open p_cursor for
select * from table ( personroles_recs );
END GET_PERSONROLES;
This code uses a second collection to store the desired output. Like your code it reads the populated collection and evaluates the attributes of each row. If a value which means the criteria it sets an attribute in a rowtype variable. If one or both attributes are set it populates a new row in a second collection. At the end of the procedure it opens the ref cursor using a table() function call on the second collection.
Note that you do not need the nested loop: you're not using the LIMIT clause so your coder reads the entire cursor into the collection in one swoop.
The implemented rules may not be exactly what you want (because you haven't explained exactly what you want) but this should give you the general idea.
Note that, depending on exactly what processing is masked by <DO SOME LOGIC AND ASSIGN THE VALUE TO THE ROW>, the simpler approach could still be feasible:
open P_CURSOR for
select case when IS_MANAGER_LEVEL1 = 'Y' then 'YES' else 'NO' end,
case when IS_MANAGER_LEVEL2 = 'Y' then 'YES' else 'NO' end
from table ( PERSONROLES_TABLETYPE );

Oracle table type to nested table cast error

I declared table type and set a value in it with using loop. I am having an error while I was casting this t_table
DECLARE
TYPE t_row IS RECORD
(
id NUMBER,
description VARCHAR2(50)
);
TYPE t_table IS TABLE OF t_row;
l_tab t_table := t_table();
BEGIN
FOR i IN 1 .. 10 LOOP
l_tab.extend();
l_tab(l_tab.last).id := i;
l_tab(l_tab.last).description := 'Description for ' || i;
END LOOP;
SELECT * from TABLE(CAST(l_tab AS t_table));
END
Best regards
Why do you want to do a select onto the the type? You would use the the TABLE() and the CAST rather if you have a collection in a column stored in a table.
You could just loop through the table in your code. Example:
for i in l_tab.first .. l_tab.last
loop
dbms_output.put_line(l_tab(i).id||' '||l_tab(i).description);
end loop;
Since l_tab is of type t_table, there's no need for the cast. But that's not your problem.
Your problem is that you're trying to reference a PL/SQL type in SQL, which you simply can't do. You can either remove the select as #hol suggested or make the type a database object (which will allow SQL to access it):
CREATE OR REPLACE TYPE t_row AS OBJECT
(
id NUMBER,
description VARCHAR2 (50)
);
CREATE OR REPLACE TYPE t_table AS TABLE OF t_row;
DECLARE
l_tab t_table := t_table ();
BEGIN
FOR i IN 1 .. 10 LOOP
l_tab.EXTEND ();
l_tab (l_tab.LAST) := t_row (i, 'Description for ' || i);
END LOOP;
FOR r IN (SELECT * FROM TABLE (l_tab)) LOOP
DBMS_OUTPUT.put_line (r.id);
END LOOP;
END;
There is a second problem with the initial code, in that you are running a select without telling the code what to do with it. Unlike some other procedural SQL extensions, PL/SQL does not allow you to implicitly return a handle to a resultset (prior to 12c). You must either handle it directly or explicitly return a ref_cursor that points to it. The code above has been update to primitively handle the result of the query.

Cursor design and refactoring question

I have many cursors that all return rows with the same fields: a numeric ID field and an XMLType field. Every time I access one of these cursors (each cursor has now got its own function for access), I go through the same pattern:
--query behind cursor is designed to no more than one row.
for rec in c_someCursor(in_searchKey => local_search_key_value) loop
v_id := rec.ID
v_someXMLVar := rec.XMLDataField
end loop;
if v_someXMLVar is null then
/* A bunch of mostly-standard error handling and logging goes here */
end if;
exception
/* all cursor access functions have the same error-handling */
end;
As the pattern became more obvious, it made sense to centralize it in a single function:
function fn_standardCursorAccess(in_cursor in t_xmlCursorType, in_alt in XMLType) return XMLType is
v_XMLData XMLType;
begin
dbms_application_info.set_module(module_name => $$PLSQL_UNIT, action_name => 'fn_standardCursorAccess');
loop
fetch in_cursor
into v_XMLData;
exit when in_cursor%notfound;
end loop;
/*some additional standard processing goes here*/
return v_XML;
exception
/*standard exception handling happens here*/
end;
The problem I've run into is in calling this function. I now have to call it like this:
open v_curs for select /*blah blah blah*/ where key_field = x and /*...*/;
v_data := fn_standardCursorAccess(v_curs,alt);
close v_curs;
What I'd like to do is call it like this:
open v_curs for c_getSomeData(x);
v_data := fn_standardCursorAccess(v_curs,alt);
close v_curs;
...reason being to minimize the amount of changes to my code (I don't want to have to cut/paste all these cursors to the functions that depend on them, and in the case where multiple functions depend on the same cursor, I'll have to wrap that in a new function).
Unfortunately, this does not work, Oracle returns an error saying
Error: PLS-00222: no function with name 'C_GETSOMEDATA' exists in this scope
Is what I'm trying to do even possible?
(Oracle version is 10.2)
EDIT:
I think a better way to describe what I'm doing is pass a reference to an explicit cursor to a function that will perform some common routines on the data returned by the cursor.
It appears that I cannot use an open-for statement with an explcit cursor, is there any other way to get a reference to an explicit cursor so I can pass that reference to a function? Maybe there is some other way I could approach this problem?
EDIT:
Copying and pasting from my earlier reply to R Van Rijn's reply:
I tried declaring the cursor in the package specification, and referencing it with the package name: open v_curs for PKG.c_getSomeData(x);... This gives me a new error, saying that PKG.c_getSomeData must be a function or array to be used that way.
UPDATE:
I spoke to our DBA here, he says it is not possible to have a ref cursor point to an explicit cursor. It looks like I can't do this after all. Bummer. :(
concerning the Error PLS-00222:
An identifier being referenced as a function 'c_getSomeData' was not declared or actually represents another object (for example, it might have been declared as a procedure).
Check the spelling and declaration of the identifier. Also confirm that the declaration is placed correctly in the block structure
This means you must create a function that actually returns some value(s).
Does this test script and output represent what you are trying to do? Instead of open v_curs for c_getSomeData(x); I'm setting the cursor variable = to the output from the function.
Our Test Data:
set serveroutput on
--create demo table
drop table company;
create table company
(
id number not null,
name varchar2(40)
);
insert into company (id, name) values (1, 'Test 1 Company');
insert into company (id, name) values (2, 'Test 2 Company');
insert into company (id, name) values (3, 'Test 3 Company');
commit;
Create Packages
create or replace package test_pkg as
type cursor_type is ref cursor;
function c_getSomeData(v_companyID number) return cursor_type;
end test_pkg;
/
create or replace package body test_pkg as
function c_getSomeData(v_companyID number) return cursor_type
is
v_cursor cursor_type;
begin
open v_cursor for
select id,
name
from company
where id = v_companyID;
return v_cursor;
end c_getSomeData;
end test_pkg;
/
Run Our Procedure
declare
c test_pkg.cursor_type;
v_id company.id%type;
v_name company.name%type;
begin
c := test_pkg.c_getSomeData(1);
loop
fetch c
into v_id, v_name;
exit when c%notfound;
dbms_output.put_line(v_id || ' | ' || v_name);
end loop;
close c;
end;
/
1 | Test 1 Company
PL/SQL procedure successfully completed.
I confess to finding your requirements a trifle hard to divine. You have posted a lot of code, but as I suggested in my comment, not the parts which would illuminate the problem. So possibly the following is way off-beam. But it is an interesting issue.
The following code shows how we can define a common, geneneric REF CURSOR, populate it with specific data from different queries, and then process them in a standardised fashion. Again, I apologise if this does not fit your business logic; if such is the case, please edit your question to explain where I have made a bloomer..
Here is the generic ref cursor. ...
create or replace package type_def is
type xml_rec is record (id number, payload xmltype);
type xml_cur is ref cursor return xml_rec;
end type_def;
/
and here is the standatd processor
create or replace procedure print_xml_cur
( p_cur in type_def.xml_cur )
is
lrec type_def.xml_rec;
begin
loop
fetch p_cur into lrec;
exit when p_cur%notfound;
dbms_output.put_line('ID='||lrec.id);
dbms_output.put_line('xml='||lrec.payload.getClobVal());
end loop;
close p_cur;
end print_xml_cur;
/
Two procedures which return the standard cursor with different data....
create or replace function get_emp_xml
( p_id in emp.deptno%type )
return type_def.xml_cur
is
return_value type_def.xml_cur;
begin
open return_value for
select deptno
, sys_xmlagg(sys_xmlgen(ename))
from emp
where deptno = p_id
group by deptno;
return return_value;
end get_emp_xml;
/
create or replace function get_dept_xml
( p_id in dept.deptno%type )
return type_def.xml_cur
is
return_value type_def.xml_cur;
begin
open return_value for
select deptno
, sys_xmlagg(sys_xmlgen(dname))
from dept
where deptno = p_id
group by deptno;
return return_value;
end get_dept_xml;
/
Now let's put it all together ....
SQL> set serveroutput on size unlimited
SQL>
SQL> exec print_xml_cur(get_emp_xml(40))
ID=40
xml=<?xml
version="1.0"?>
<ROWSET>
<ENAME>GADGET</ENAME>
<ENAME>KISHORE</ENAME>
</ROWSET>
PL/SQL procedure successfully completed.
SQL> exec print_xml_cur(get_dept_xml(20))
ID=20
xml=<?xml version="1.0"?>
<ROWSET>
<DNAME>RESEARCH</DNAME>
</ROWSET>
PL/SQL procedure successfully completed.
SQL>
OK, so the short answer from Oracle is: "can't be done!"
The short answer from me is: "Yeah - like Oracle is gonna stop me! So yes you can....but you need to be sneaky ... oh yes, and there is a 'but' or two....in fact...ugh!"
So, how can you pass your explicit cursor by reference? By nesting it into another cursor using the CURSOR() construct!
e.g.)
CREATE OR REPLACE package CFSDBA_APP.test_Cursor
as
function get_cursor(ed_id number) return sys_refcursor;
end;
/
CREATE OR REPLACE package body CFSDBA_APP.test_Cursor
as
function get_cursor(ed_id number) return sys_refcursor
is
test_Cur sys_refcursor;
cursor gettest is
select CURSOR( -pass our actual query back as a nested CURSOR type
select ELCTRL_EVNT_ELCTRL_DISTRCT_ID,
ELECTORAL_DISTRICT_ID,
ELECTORAL_EVENT_ID
from ELCTRL_EVNT_ELCTRL_DISTRCT
where electoral_District_id = ed_id)
from dual;
begin
open gettest;
fetch gettest into test_Cur;
return test_Cur;
end;
end;
/
So what is the problem with this solution? It has a leak! The outer gettest cursor is never closed, because we don't close it and the client will only close the reference to the nested cursor that was selected for them - not the main cursor. And we can't close it automatically because closign the parent would force closing the nested cursor that you have returned by reference - and it is entirely likely that the client has not done using it.
So we have to leave a cursor open in order to return the nested cursor.
And if the user tried calling get_Cursor again with a new value of ed_id, they would discover that the session persistence in the package meant that the cursor handle is still in use and an error would be raised.
Now, we could fix that by first checking and closing the explicit cursor:
if gettest%isopen then
close gettest;
end if;
open gettest;
fetch gettest into test_Cur;
return test_Cur;
But still - what if the user never calls this again? How long 'til Oracle garbage-collects the cursor? And how many users running how many sessions calling how many functions that use this construct will be leaving cursors open after they are done with them? Better count on a huuuuuge overhead to leave all those open cursors layin' about!
No, you would need to have the users do a callback to explicitely close it or you would be clogging the database. But doing this would require changing the scope of the explicit cursor so that both functions can access it: So we need to make it at package scope, not function scope
CREATE OR REPLACE package CFSDBA_APP.test_Cursor
as
function get_cursor(ed_id number) return sys_refcursor;
function close_cursor return sys_refcursor;
end;
/
CREATE OR REPLACE package body CFSDBA_APP.test_Cursor
as
cursor l_gettest(p_ed_id in number) is
select CURSOR(
select ELCTRL_EVNT_ELCTRL_DISTRCT_ID, ELECTORAL_DISTRICT_ID, ELECTORAL_EVENT_ID
from ELCTRL_EVNT_ELCTRL_DISTRCT
where electoral_District_id = p_ed_id)
from dual;
function get_cursor(ed_id number) return sys_refcursor
is
l_get_Cursor sys_refcursor;
begin
open l_gettest (ed_id);
fetch l_gettest into l_get_Cursor;
return l_get_cursor;
end;
function close_cursor return sys_refcursor
is
begin
if l_gettest%isopen then
close l_gettest;
end if;
return pkg_common.generic_success_cursor;
end;
end;
/
OK, plugged the leak. Except it cost us a network round trip instead of the hard parse,...oh wait - and also except embedding a bind variable into an explicit cursor declared at this level is probably going to cause scoping issues of its own which was the reason we wanted to do this in the first place!
Oh, and in a session-pooling environment can two users step on each other's cursors? IF they aren't very carefull about doing an open-fetch-close before returning the session to the pool - we could wind up with some really interesting (and impossible to debug) results!
And how much do you trust the maintainers of the client code to be extra-diligent on this? YEah - me too.
So the short answer is: Yes, with a bit of sneakiness it could be done despite Oracle saying it can't.
The better answer is: But please don't! The extra round trip and potential for memory leaks and client code errors causing data problems makes this a very scary proposition.
It appears that what I wanted to do (have an open-for statement reference an existing explicit cursor) is simply not allowed in Oracle. :(

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