Is this a right approch

Question

I am not sure whether I can ask like this or not...We are working on JAVA/Oracle(10.2) platform and using Ref cursors to pass the records from Oracle to Java (like Report kind of Application activities in Java) and we employed following code structure
IF a='ALL' THEN
Open RefCur for
SELECT....
ELSIF a=p_a THEN
Open RefCur for
SELECT....
ENDIF;
RETURN RefCur;
CLOSE RefCur;
We are ensuring at Application level(Screen flow) that it should not pass the value other then the mentioned coded condition (like NULL). I am not sure whether this approch is a good practice ? I am worried about returning and closing .
Apprtiate all comments.
Thanks and Regards
Mai.

Answer 1

OK, to make it short:
The correct approach for the problem where you have different SQL-statements depending on some conditions, is given by Tom Kyte (from AskTom). This is the one to choose.
If you have a "static" SQL i.e. just condition will change, you could use the following code snippet
SQL> var ec refcursor
SQL> set autoprint on
SQL> create or replace procedure test (p_empno in number, rc out sys_refcursor) is
  2    l_stmt   varchar2(1000);
  3  begin
  4    l_stmt := 'select ename, empno from emp where empno = :x';
  5    open rc for l_stmt using p_empno;
  6  end;
  7  /
Procedure created.
SQL>
SQL> exec test(7788, :ec);
PL/SQL procedure successfully completed.
ENAME                               EMPNO
SCOTT                                7788
1 row selected.
SQL>
SQL> exec test(4711, :ec)
PL/SQL procedure successfully completed.
ENAME                               EMPNO
that's ME                            4711
1 row selected.
SQL>