Re: COBOL400-L Digest, Vol 9, Issue 9

[Chuck Landress <clandress@xxxxxxxxxxx>]

Using SQL to access DDS defined files shouldn't degrade performance
seriously but you will see a performance improvement  from your programs
using both SQL and record level I/O if you redefine them with DDL.  One of
the reasons for the performance increase is that indexes are processed in
larger blocks when files are defined using DDL.

Be sure you have indexes built with the keys you're using to access the data
or performance will suffer on files with large record counts.

Chuck Landress, PMP
678-469-2326

A creative man is motivated by the desire to achieve, not by the desire to
beat others.
 - Ayn Rand





On Tue, Jan 25, 2011 at 1:00 PM, <cobol400-l-request@xxxxxxxxxxxx> wrote:

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>   1.  Replacing Traditional I/O with SQL (Jeff Buening)
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> ----------------------------------------------------------------------
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> message: 1
> date: Tue, 25 Jan 2011 09:16:32 -0500
> from: Jeff Buening <JeffBuening@xxxxxxxxxxxxxxxxxxx>
> subject: [COBOL400-L] Replacing Traditional I/O with SQL
>
>
>  For people that have replaced traditional I/O including Read and Writes
> with SQL, was there a significant hit on performance if the underlying file
> structure was still DDS?  Just wondering if not even worth doing the
> embedded SQL, unless we switch the file to DDL.
>
> I have written some new programs that only do some selects and write to a
> print file and have been fine still DDS structure.  My concern is I start
> replacing traditonal I/O Reads and Writes and I am going to see this huge
> impact unless we switch to DDL first.  Or this is my impression I have
> gotten online.  Does my concern seem valid or has anyone done this and the
> impact not as bad as I think?
>
>
>  Thanks,
>
>   Jeff
>
>
>
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> End of COBOL400-L Digest, Vol 9, Issue 9
> ****************************************