Returning the collection Oracle SQL - oracle

So I have a function which I am trying to return a bunch of mobile numbers for each team. The problem is, the numbers being returned are all the same rather than being different for each team (see output)
screen print of output
Could you give any pointers to where I may be going wrong?
Thanks.
CREATE OR REPLACE TYPE BODY TeamType AS
MEMBER FUNCTION get_tel_num (numberType IN VARCHAR2)RETURN VARCHAR2 IS
prefix VARCHAR2(5);
d_code VARCHAR2(4);
main_number VARCHAR2(7);
CURSOR team_cursor IS
SELECT ta.intl_pref, ta.dial_code, ta.p_number
FROM Team t, Table(t.tel_nos) ta
WHERE ta.number_type = numberType;
BEGIN
IF NOT team_cursor%ISOPEN THEN
OPEN team_cursor;
END IF;
LOOP
FETCH team_cursor INTO prefix, d_code, main_number;
EXIT WHEN team_cursor%NOTFOUND;
RETURN prefix ||'-'|| d_code ||'-'|| main_number;
END LOOP;
CLOSE team_cursor;
END;
END;

Looking at the design on your function's signature:
Input: numberType (e.g. mobile)
Output: VARCHAR2 (i.e. the number)
Given that, and the definition of your WHERE statement at the team_cursor, there is no way for your function to know whom this number is for. Therefore, based on your LOOP body, you just return the first result of your cursor, which happens to be the same number with every call you make to the function.
One solution to that is to add one more parameter to your function that takes an identifier of the team member to which the inquired phone number belongs. Use this parameter in your WHERE statement of the team_cursor to get the number of that particular team member.

You might want to return a cursor so that the calling program can fetch all of the rows.
http://docs.oracle.com/database/121/LNPLS/static.htm#LNPLS494

Related

Better to call functions repeatedly or store function result in variable for reuse in plsql procedure

Is it best practice / more efficient to call a defined function several times within a procedure or to store the function result in a local variable and use the held variable value instead?
The value returned from within the function is a date value.
(select start_date from extract_dates)
It is definitely a good idea to call the function once and reuse the returned value many times if possible - e.g. when looping:
declare
l_start_date date;
begin
l_start_date := get_start_date_for_dept (10);
for r in (select id from big_table) loop
process_record (r.id, l_start_date );
end loop;
end;
Here the function is called once rather than as many times as big_table has rows. If each call takes a millisecond, and big_table has 10,000 rows then calling the function inside the loop could add 10 seconds to the overall run-time. This is just standard programming good practice.

error on calling function by procedure

I coded for the function, and calling procedure below. Both of coding is possible to execute, but when I exec ProdDetails(10010), it show error. Can anybody know what are problems?
create or replace function ProdCheck(
f_product_id in number)
return varchar IS
f_product_name varchar(30);
f_product_price number;
begin
select product_name, price into f_product_name, f_product_price
from product
where product_id = f_product_id;
return f_product_name;
end;
create or replace procedure ProdDetails(
sp_product_id in number
)IS
f_product_id number;
sp_name varchar(30);
sp_price number;
begin
f_product_id := ProdCheck(sp_product_id);
if f_product_id > 0 then
dbms_output.put_line('Product Name : '||sp_name);
dbms_output.put_line('Product Price : '||sp_price);
else
dbms_output.put_line('Product not in the database!');
end if;
end;
Your function prodcheck takes a product_id and returns the product_name. Then in the procedure you call the function, you feed the function a product_id (everything fine so far), but then assign the return value from the function, which is the product name, to the variable f_product_id, which you declared as number. Obviously that won't work. And, indeed, the function and the procedure are both syntactically correct; only when you put them together will this fail, and only at runtime since Oracle doesn't strictly enforce data types (if the product name was '1000' instead, perhaps the function would execute OK - and produce garbage results since it would interpret this product name as the product id instead).
You query your table in the function to check if the product id is valid, and you return the name. In the procedure, you could assign the return value from the function to sp_name. The function does not return the price though (it can't - a function cannot return more than one value), so you can't display the price in the procedure. You could query the table again in the procedure, but that seems pretty senseless; it would be better to combine everything into a single procedure. (You probably don't need the check at all - if the product id doesn't exist in the table, you will get a "no rows" exception and you can use that instead of prodcheck.)

How to retrieve values post-execution of PL/SQL stored procedure?

Im very new to oracle database stuff. There is a PL/SQL proceedure which someone else wrote and is stored on the database I am accessing. I want my program to execute it and retrieve the result. Execution is working. I cannot retrieve the result however. Obviously I am not doing it right, but I cannot find the right way in the documentation.
Here is the gist of the stored procedure (with extraneous lines removed)
procedure ISDRAWINGVALID(DWGNO_IN in VARCHAR2) is
valid BOOLEAN;
begin
-- do some stuff to see if the drawing is valid
IF <some stuff> THEN
valid := TRUE;
ELSE
valid := FALSE;
END IF;
END ISDRAWINGVALID;
My program issues the following commands to the database to execute and retrieve the return.
BEGIN ISDRAWINGVALID( <drawingnumber> ); END;
SELECT ISDRAWINGVALID.valid FROM DUAL;
The first line works fine, the proceedure executes and has the desired effect.
The second line returns an error, invalid identifier "ISDRAWINGVALID.valid"
Clearly i am not using the right way to retrieve the value. Can someone please clue me in?
thanks
As you present the problem, there is no way to get the result.
If you can get the procedure as a function instead, you can call it directly in the select statement.
Otherwise you would have to take a long detour to solve it, involving a result table or a pl/sql package with a result function and a package variable.
The procedure you have there has been made to be called from other pl/sql code - not in a select query.
EDIT
I think I might be wrong after all.
In Java you can create a prepared statement with a call, and pick up the return value directly as a result-set.
Check this out and come back with the result: http://archive.oreilly.com/pub/a/onjava/2003/08/13/stored_procedures.html?page=2
Sorry if you are not using Java, I was not able to see what you are using.
Use a function and return a NUMBER to be used in SQL:
CREATE OR REPLACE
FUNCTION ISDRAWINGVALID(DWGNO_IN in VARCHAR2) RETURN NUMBER
IS
valid NUMBER;
BEGIN
IF <some stuff> THEN
valid := 1;
ELSE
valid := 0;
END IF;
RETURN valid;
END ISDRAWINGVALID;
Use from PL/SQL:
DECLARE
valid NUMBER;
BEGIN
valid := ISDRAWINGVALID( <drawingnumber> );
END;
/
Use from SQL:
SELECT ISDRAWINGVALID( <drawingnumber> ) FROM DUAL;

How to declare / assign a variable to a cursor type in PL/SQL procedure

I have two cursors declared in a stored procedure (inside a package).
procedure RECONCILE_CC_TRX (p_to_date in date,
p_nz_flag in varchar2,
p_Reconcile_Header_ID out NUMBER
) is
CURSOR LOADED_TRXS_AU IS
SELECT
CC_REC_LOAD_TRX_ID,
CC_REC_LOAD_HEADER_ID,
....
CURSOR LOADED_TRXS_NZ IS
SELECT
CC_REC_LOAD_TRX_ID,
CC_REC_LOAD_HEADER_ID,
The only difference between the two cursors is the where clause.
What I want to do, is open one of those cursors based on the p_nz_flag passed in above. ie:
IF NVL(p_nz_flag, 'F') = 'F' THEN
v_load_trx_cursor := LOADED_TRXS_AU;
ELSE
v_load_trx_cursor := LOADED_TRXS_NZ;
END IF;
FOR bitem IN v_load_trx_cursor LOOP
...
My initial thinking was to declare a variable and assign it the appropriate cursor, however, I can't get the procedure to compile with this. eg, I have tried:
v_load_trx_cursor sys_refcursor;
but I get a compilation error when assigning v_load_trx_cursor of "PLS-00382: Expression is of wrong type". If I change my declaration to:
v_load_trx_cursor cursor;
I get compilation error at the declaration point stating "PLS-00201: Identifier 'Cursor' must be declared.
Is it possible to do what I want to do? At the end of the day, I just want to iterate the appropriate cursor based on the p_nz_flag parameter passed in.
Thanks
It looks like you want to use only one cursor in your code, based on the value of p_nz_flag
In this case, believe it will be better to make the where clause dynamically in your code and then use refcursor to return the data of the query.
Something like given in Example 7-4 on this link Dynamic Query with Refcursor
Hope it Helps
Vishad
Hi if your whole work for doing this procedure is just to populate the appropriate cursor i think this code may help you.
CREATE OR REPLACE PROCEDURE av_nst_cursor(
flag_in IN VARCHAR2,
av_cur OUT sys_refcursor)
AS
BEGIN
IF flag_in = 'Y' THEN
OPEN av_cur FOR SELECT Query;
ELSE
OPEN av_cur FOR SELECT query;
END IF;
END;

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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