Re: Chain vs SetLL/ReadE

On Wed, 2008-09-03 at 21:29 -0400, Barbara Morris wrote:

Terrence Enger wrote:

...
Did you really receive that recommendation in freeform? I took
Barbara's second comment in
<http://forums.systeminetwork.com/isnetforums/showthread.php?t=52004>
to mean that the difference does not matter in ILE/RPG.

I think you mean was my third comment in that thread (the one starting
with "I don't know if it was ever correct".

I didn't mean to imply that the difference doesn't matter; I'm not
expert enough to say that with any authority. I think there are some
cases where SETLL beats CHAIN and vice versa; things I don't recall
clearly or understand, related to the sparseness of the keys in the file.

What's different between ILE RPG and OPM RPG is that for
record-not-found, CHAIN doesn't have the performance penalty that OPM
RPG has. So in the cases where the nature of the file might make CHAIN
and SETLL perform significanly differently, the difference would be ...
um ... different between ILE RPG and OPM RPG.

Thank you, Barbara. I was reading with too many preconceptions.

I should have said, on the off-chance that anybody cares, that I intend
not to think very much about the relative performance until the
difference shoves itself in my face.

Cheers,
Terry.