How to return a table from function

Question

Hi,
I want to return a table from the function. But i'm unable to do it.
can any one give me a peice of code.
Thanks in advance.
Regards,
Alok

Answer 1

Are you referring to a pipelined table function?
Here is an example of such a function returning a "hailstone" sequence.. a number range that always end in 4,2,1. (see the [url http://en.wikipedia.org/wiki/Collatz_conjecture]Collatz Conjecture for more details on the maths used).
SQL> create or replace type TNumbers is table of number;
2 /
Type created.
SQL>
SQL> create or replace function hailstone( nValue number ) return TNumbers pipelined is
2 n number;
3 begin
4 n := nValue;
5 loop
6 PIPE ROW( n );
7 exit when n = 1;
8
9 if MOD(n,2) != 0 then
10 n := (n * 3) + 1;
11 else
12 n := n / 2;
13
14 end if;
15 end loop;
16 end;
17 /
Function created.
SQL> show errors
No errors.
SQL>
SQL>
SQL> select * from TABLE( hailstone(10) );
COLUMN_VALUE
10
5
16
8
4
2
1
7 rows selected.
SQL> select * from TABLE( hailstone(1923413) );
..etc.