Re: pipelined always better?

thorsten.kettner_at_web.de (Thorsten Kettner) wrote:

>I have written a small function which returns a table of numbers.
>However there are two approaches as to return the table: either
>pipelined or not.
>
>My Oracle book tells me that pipelining is better, because it delivers
>the rows immediately instead of waiting for the whole collection to be
>complete. That makes sense for example if I select with "where rownum
>< ...". But elsewise? Isn't data transfered from the db server in big
>chunks anyhow? Can the non-pipelined way be more efficient than the
>pipeline way hence?
>
>=======================================
>1. approach returning a pipelined table
>=======================================
>
> Function GetNumbers(p_min IN number
> ,p_max IN number) RETURN t_numbers pipelined IS
>
> BEGIN
> for i in p_min .. p_max loop
> pipe row(i);
> end loop;
>
> return;
> END; -- Function GetNumbers
>
>===========================================
>2. approach returning a non-pipelined table
>===========================================
>
> Function GetNumbers(p_min IN number
> ,p_max IN number) RETURN t_numbers IS
>
> v_numbers t_numbers;
>
> BEGIN
> v_numbers := t_numbers();
> for i in p_min .. p_max loop
> v_numbers.extend;
> v_numbers(v_numbers.count) := i;
> end loop;
>
> return v_numbers;
> END; -- Function GetNumbers

Instead of theorizing, why not test both and examine the results? Received on Thu Sep 11 2003 - 09:46:48 CDT