RE: READE vs. READPE performance

Hi Greg,
I have to read records by Company and Route first, so don't I need to use
READE or READPE?  I can't assume the records will be sequential.

Example assuming Date is keyed ascending:

Company = 'B1';
Route = 15;
Date = %date();
setgt (Company : Route : Date) LOGICAL1;

dou %eof(LOGICAL1);
      readpe (Company : Route) LOGICAL1;
      if not %eof(LOGICAL1);
            // Process this record
      endif;
enddo;




                                                                           
             "Fleming, Greg                                                
             \(ED\)"                                                       
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                                                                   Subject 
                                       RE: READE vs. READPE performance    
             12/09/2005 02:08                                              
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If performance is an issue, don't use READE or READPE.

SetGT and ReadP.

I don't know if that is any faster or slower than reading forward, but I
can't think of any reason why there would be any difference.



>-----Original Message-----
>From: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx]
>On Behalf Of Ben_Pforsich@xxxxxxxxxxxx
>Sent: Friday, December 09, 2005 2:03 PM
>To: rpg400-l@xxxxxxxxxxxx
>Subject: READE vs. READPE performance
>
>
>Generally speaking, has anyone tried or know for a fact which of the
>following scenarios result in better performance (faster I/O?)?...
>1.  READE on logical with a descending key  (ex:  READE (Company :
Route :
>Date) LOGICAL1 where Date is keyed descending)
>2.  READPE on logical with an ascending key  (ex: READPE (Company :
Route :
>Date) LOGICAL2 where Date is keyed ascending).
>
>I want to read records in a history transaction file keyed with a date
>field starting with the most recent and going backward.  I'm trying to
>decide whether I should build a new logical over a fairly large
physical,
>or use an existing logical and use READPE instead of READE.  I will be
>likely reading potentially 10,000 to 50,000 records in one pass and
>performance is an issue.
>
>Let me know if you need more information, but I was hoping for a quick
and
>dirty response.
>
>Thanks!
>
>Ben Pforsich
>Programmer Analyst
>Bob Evans Farms, Inc.
>I/S Department
>Columbus, Ohio
>Ben_Pforsich@xxxxxxxxxxxx
>
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