RE: Program performance incease ideas

Brian,
        One approach could be to sum all records first then match the two.
The main problem I see if that the query engine MUST cover the indexes for
each read of MyFile.  

How about:

        DECLARE SUMCSR CURSOR FOR SELECT summary data FROM file
group by FIELDS,,,
        
        OPEN SUMCSR
        
        DO WHILE SQLSTT = '00000'
                FETCH FROM SUMCSR
                CHAIN TO MYFILE
                UPDATE SUM FIELD
        ENDDO

This way the query engine will only go over the index one time.  

Thank you,
Matt Tyler
WinCo Foods, LLC
mattt@xxxxxxxxxxxxxx


-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx [mailto:rpg400-l-bounces@xxxxxxxxxxxx]
On Behalf Of Brian Piotrowski
Sent: Tuesday, July 19, 2005 8:10 AM
To: RPG programming on the AS400 / iSeries
Subject: Program performance incease ideas

Hi All,

 

I have a portion of one of my programs that does this:

 

Read Myfile

Do while not eof(Myfile)

  Read Myfile

  SQLSum = Get the sum of a series of records where somepart = current part#
and somecolour = current part colour

  NewSum = CurrentSum - SQLSum

  Update Myfile

  Read Myfile

EndDo

 

I find this process to be very time-consuming, as each SQL transaction takes
about 2-7 seconds to complete.  I'm using a logical file to get the data
that is keyed on the part number and colour as well as only selecting
records that have a status of 3 or 5.

 

Any ideas on how I could speed this up?  The physical file which it is
updating only has 1400 records in it, and it's been running now for the past
½ hour and has less than ½ the records processed.

 

Thanks,

 

Brian. 

 

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Brian Piotrowski

Specialist - I.T.

Simcoe Parts Service, Inc.

Ph: 705-435-7814 x343

Fx: 705-435-6746

bpiotrowski@xxxxxxxxxxxxxxx

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