Order by clause in PL/SQL cursors

Question

I am trying to execute a procedure with some input parameters. I open a cursor
with a select statement. However, the order by clause in the query does not
recognize parameter sent through the procedure input parameters.
For example:
open <<cursor name>> for
select id from member order by <<dynamic parameter>>" does not work (Compiles fine but does not return the right result).
But if I try and give a static order by <<column name>> it works. Is the
order by clause in the PL/SQL a compile time phenomenon?
I have also tried it through dynamic sql. All the other parameters work except the order by <<parameter>> asc|desc
Also "asc" and "desc" does not work if given dynamically.
What alternatives do I have?
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Answer 1

I don't think order by can be dynamic in a cursor, but it sure can be using dynamic sql. The only issue is that you must do a replace in the sql string with the dynamic variable. For example:
create or replace procedure test_dyn(p_col in varchar2, p_order in varchar2) as
q varchar2(500);
u_exec_cur number;
u_columnnumber NUMBER;
u_columndate DATE;
u_columnvarchar varchar2(50);
u_cur_count number;
u_ename varchar2(20);
u_sal number;
begin
q := 'select ename, sal from scott.emp order by p_col p_order';
-- got to do these two replaces
q:= replace(q,'p_col',p_col);
q:= replace(q,'p_order',p_order);
u_exec_cur := dbms_sql.open_cursor;
dbms_sql.parse(u_exec_cur,q,dbms_sql.v7);
dbms_sql.define_column(u_exec_cur, 1, u_columnvarchar, 20);
dbms_sql.define_column(u_exec_cur, 2, u_columnnumber);
u_cur_count := dbms_sql.execute(u_exec_cur);
loop
exit when (dbms_sql.fetch_rows(u_exec_cur) <= 0);
dbms_sql.column_value(u_exec_cur, 1, u_ename);
dbms_sql.column_value(u_exec_cur, 2, u_sal);
dbms_output.put_line(u_ename);
dbms_output.put_line(u_sail);
--htp.p(u_ename);
--htp.p(u_sal);
end loop;
end;
show errors;
Now when when I execute my procedure I can change the order by clause all I want, for example:
SQL> set serveroutput on;
SQL> exec gmika.test_dyn('sal','asc');
SMITH
800
ADAMS
1100
WARD
1250
MARTIN
1250
MILLER
1300
TURNER
1500
ALLEN
1600
JLO
2222
BLAKE
2850
JONES
2975
SCOTT
3000
FORD
3000
LOKITZ
4500
KING
5000
JAMES
5151
JAMES
5555
PL/SQL procedure successfully completed.
SQL>
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