Re: Master file vs. Work file

[Glenn Ericson <Glenn-Ericson@xxxxxxxxxxxxxxxx>]

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I am  not sure  what the difference in size is between the 100,000  record
master  file and the reference to  a HUGE master file.

This  ad-hoc reporting  you are doing ?

Fewer reads [ file accesses] by  query the better

At 10:14 AM 9/2/2002 +0000, Deepak Deshpande wrote:
>Hello everybody,
>
>I have to create a report of most popular products based on sales amount
>in a given period.
>
>Case 1
>1.      Read an OPNQRYF based on a master file (@ 100,000 records in
>master file)
>2.      Write work file based on the selection (@ 1000 records)
>3.      Read work file with key1 (@ 1000 records)
>4.      Do some processing
>5.      Read work file with key 2 (@ 1000 records)
>6.      Print report
>
>Case 2
>1.      Read an OPNQRYF based on a huge master file
>2.      Write work file based on the selection (@ 10 records, yes only 10
>records)
>3.      Read work file with key 1 (@ 10 records)
>4.      Do some processing
>5.      Read OPNQRYF based on the same huge master file (Will it read only
>1000 records selected by OPNQRYF or read again the whole file?)
>6.      Print report
>
>Which is the better option? Reading master file twice OR writing work file
>with more records (10 vs. 1000) and read it?
>
>TIA,
>Deepak
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