Re: Seeking recursive solution to replace nested for-loops

"Michelle Romano" <mromano_at_sensis.com> wrote in message news:aaba7f35.0402190919.31edd67f_at_posting.google.com...
| Working with PL/SQL and Oracle9i, I am looking for a better way to
| generate combinations of n objects taken k at a time:
| n!/k!(n-k)!
| I am currently using the nested for-loop concept, but it is very
| inefficient since the value of k can vary.
|
| Does anyone know of a recursive solution or a better iterative
| solution using PL/SQL? Even a code sample which demonstrates
| recursion would give me a good place to start.
|
| Thanks in advance for your help.
|
| Michelle

real simple recursion example:

create or replace procedure recurse ( ip_levels in number ) is
begin

    dbms_output.put_line( ip_levels );
    if ip_levels > 0
    then

        recurse(ip_levels-1);
    end if;
    dbms_output.put_line( 'exiting ' || ip_levels ); end recurse;
/

set serveroutput on

exec recurse(10)

10
9
8
7
6
5
4
3
2
1
0
exiting 0
exiting 1
exiting 2
exiting 3
exiting 4
exiting 5
exiting 6
exiting 7
exiting 8
exiting 9
exiting 10

;-{ mcs Received on Fri Feb 20 2004 - 18:14:11 CET