RE: CHAIN to a DS

[CWilt@xxxxxxxxxxxx]

Couple of things.

1) Instead of CHAIN, try SETLL as it does not read the record into the
buffer.

2) instead of Native I/O check out SQL, with the proper indexes it should be
even faster.

insert into updfile (select * from origfile
                           where key not in (select key from updfile)
                          )

Also, may want to try using the EXISTS predicate.  I'm not real good with
its use but something like:

insert into updfile A ( select * from origfile B
                               where not exists ( select 1 from updfile C
                                                          where B.key =
C.key)
                             )

HTH,
Charles


> -----Original Message-----
> From: CarollaT@xxxxxxxxxxxxxx [mailto:CarollaT@xxxxxxxxxxxxxx]
> Sent: Friday, September 03, 2004 11:16 AM
> To: rpg400-l@xxxxxxxxxxxx
> Subject: CHAIN to a DS
> 
> 
> I have written some code that takes records in a temp file, and either
> updates or adds them to another file.  It's the same old, "If 
> the record
> exists, update, else write" scenario.  The top factor for 
> this little module
> is speed - We want this thing to scream, so I am trying to 
> cut every corner
> I can, then I will document the you-know-what out of it later.  
> 
>  
> 
> Basically, I have the output/update file prefixed with a 'D', 
> and I read the
> input record, attempt a chain to the output/update file, and 
> move the fields
> (450+) from the input file to the output file (in case the 
> chain found a
> record), and conditionally write or updated, based on %FOUND.  
> 
>  
> 
> So I am thinking about this, and I know that you can CHAIN, 
> and read the
> resulting record into a data structure.  What I am wondering 
> is, since both
> files have the same format, and field names, can I CHAIN to the
> output/update file, but read the record in to a DS, and _not_ 
> udpate the
> fields in the record format.  Does every successful chain 
> have to send the
> fields to the input record fields?  If not, then I would 
> attempt the chain,
> and skip moving the 450+ fields to the output buffer, with 
> the prefix.  
> 
>  
> 
> Thanks in advance for your help.  
> 
>  
> 
> Tony Carolla
> 
> MedAmerica Billing Services, Inc.
> 
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