Re: Using Members within a PF

Multiple member physical files are useful in applications that need to preserve
snapshots of your data at certain points in time. Preserving annual snapshots
of financial records, for example. When one fiscal year is completed, a
cut-off point is reached, and a new member is added to hold new orders and
transactions thereafter, for example. Creating a snapshot of student
enrollment records for each school year may be another example.

Since the data is partitioned into smaller units, queries and single member
backups run faster than in cases where all the records are stored in just one
member. However, you may want to weigh the performance gains against the
hassle of doing member overrides for query and maintenance purposes.


Nathan M. Andelin


----- Original Message ----
From: Brian Piotrowski <bpiotrowski@xxxxxxxxxxxxxxx>
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx>
Sent: Tuesday, July 10, 2007 7:03:37 AM
Subject: Using Members within a PF

Hi All,



I've been going through the code with a fellow programmer here at work,
and we've noticed that the original programmers created physical files
and then added members to the file. The programmers have then created a
logical file on top of the original physical file and use these members
within the RPG code.



Can some please explain what advantage there is to this practice?
Wouldn't the logical file negate the need for the members within the
physical file?



The practice of adding members to physical files does not appear to be
the case for most of the PFs in our system - only a few of the work
files exhibit this trait. Would we be better off to eliminate the
members and just use the straight LFs for our work?



Thanks,



/b;



-=-=-=-=-=-=-=-=-=-=-=-=-=-
Brian Piotrowski
Assistant Mgr. - I.T.
Simcoe Parts Service, Inc.
Ph: 705-435-7814 x343
Fx: 705-435-6746
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