Re: Setll vs. chain

[boothm@xxxxxxxxxxxxxxxxx]

Carl, how large is the formula file?  Could you load an array at *INZSR 
with all the formula indices and then  SORTA the array?  If so, then do a 
LOKUP at detail time, and if successful, only then chain to your real 
file??  Preventing file access for 90+% of the records would yield savings 
of note, I suspect.

_______________________
Booth Martin
boothm@earth.goddard.edu
http://www.spy.net/~booth
_______________________




"Carl Pitcher" <cpitcher@roadrunner.nf.net>
Sent by: owner-rpg400-l@midrange.com
02/09/2000 03:06 PM
Please respond to RPG400-L

 
        To:     <RPG400-L@midrange.com>
        cc: 
        Subject:        Setll vs. chain


We have a report program that processes a master file of 300,000+ records
which runs ever so slow.  Each record chains to a formula file to see if a
formula exists and does some calcs. Out of the total master file, there
would be no more than 1000 successful hits on the formula file.  Before I 
go
ripping this code apart (and converting it to RPGIV in the process), my
expectation is that if I change the CHAIN to a SETLL and then chain on a
successful hit that it should improve the performance considerably.  Am I
wrong in assuming that SETLL will just look at the "index" which should be
in memory as opposed to CHAIN which most often requires an access to disk 
to
retrieve the record? TIA.


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