Re: Fastest way to delete records.

[Jim Langston <jimlangston@xxxxxxxxxxxxxxxx>]

James,

It was stated that this would be run monthly or semi monthly.  Yes, for a one 
time
shot, I would just go through the records and compare each individually, then 
copy
and delete the ones that are needed.

Since he needs to do this on a regular basis, though, ones the logical file is 
built
it won't take any appreciable time to maintain it, so the next time he uses 
this 
procedure there won't be the logical build overhead.

Regards,

Jim Langston

"James W. Kilgore" wrote:
> 
> Cindy, Jim,
> 
> This might be one of those 'it depends' kind of situations.  Depending on the
> number of records that would be selected, it may take longer to build the 
>logical
> than the benefit that may be gained.
> 
> For example, since it is February, 2001 and if the entries to be deleted are 
>ALL
> year 2000, the majority of the records are subject to delete.  In this case it
> may be faster if the file can be processed sequentially.  Ideally, processed 
>with
> an OPNQRYF front end to do the filtering which would be faster than having 
>RPG do
> the filtering and avoid locking every record in the process.
> 
> Having said all of that, if the file contains 2001 and the past 10 years and 
>you
> want to remove just one year, I would still use OPNQRYF if the file can be
> processed sequentially.  The time it takes OPNQRYF to read the entire file to 
>do
> the filtering, I imagine, would be less time than CRTLF would take to read the
> entire file, filter -and- build a permanent index.
> 
> MHO
> 
> Cindy Hudson wrote:
> 
> > That's exactly what I was going to write.
> >
> > -----Original Message-----
> > From: owner-rpg400-l@midrange.com [mailto:owner-rpg400-l@midrange.com]On
> > Behalf Of Jim Langston
> 
> >
> > Hmm...
> > create a logical on the time stamp.
> >
> > Open Combined Full procedural this file
> > Do while not LR
> >   if  TimeStamp <= ToTimeStamp
> >   Delete  Record
> >   else
> >   SetOn LR
> >   EndIf
> > End Do
> >
> > Can anyone think of a faster way?
+---
| This is the RPG/400 Mailing List!
| To submit a new message, send your mail to RPG400-L@midrange.com.
| To subscribe to this list send email to RPG400-L-SUB@midrange.com.
| To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---