REF CURSOR? FUNCTION RETURN VALUE BASED ON DYN QUERY

Question

Hi to all,
i need to write a function that do the following (but have to work...):
Note: what i really don't remember is how can i have a valid cursor based using
a dynamic field taken from the input value PAR_NAME.
Hope that my problem is clear reading the NOT WORKING CODE below.
thanx a lot
CREATE OR REPLACE
FUNCTION FNC_RET_FLD_VAL(ID_CNT NUMBER, PAR_NAME VARCHAR2) RETURN VARCHAR2 AS
RETVAL VARCHAR2(300);
CURSOR FVAL IS
SELECT PAR_NAME FROM TBCONTATTI WHERE NORECORD=ID_CNT;
BEGIN
FOR REC IN FVAL LOOP
RETVAL:=REC.PAR_NAME;
END LOOP;
RETURN RETVAL;
END FNC_RET_FLD_VAL;

Answer 1

Like this ?
SQL> create function get_data(colname varchar2, empno number)
  2  return varchar2
  3  is
  4   ret varchar2(4000);
  5  begin
  6   begin
  7    execute immediate 'select ' || colname || ' from emp where empno = :1' into ret using empno;
  8   exception
  9    when no_data_found then
10     ret := null;
11   end;
12   return ret;
13  end;
14  /
Function created.
SQL> select get_data('ename',7369) from dual;
GET_DATA('ENAME',7369)
SMITH
SQL> select get_data('job',7369) from dual;
GET_DATA('JOB',7369)
CLERK
SQL> select get_data('job',-1) from dual;
GET_DATA('JOB',-1)
Rgds.