RE: CHAIN or READ without lock

I respectfully submit that if you're writing code for file updates & locking
the records (especially in subfiles or file maintenance applications),
you're building in alligators.  Consider a customer file maintenance program
for example:  the operator keys in the customer number and displays the
information for change, the phone rings and the record remains locked for
the duration of the phone call (unless it's time to go to lunch) -
meanwhile, the alligator waits to bite you in the ass because the batch job
posting invoices is just sitting in the q waiting to update the customer
balance in the locked record, which causes a program check, which gets
cancelled by the system operator, which screws up your data.  Design your
code so that you get the information without locking the record and only
lock the record when you are ready to update it.

-----Original Message-----
From: owner-rpg400-l@midrange.com [mailto:owner-rpg400-l@midrange.com]On
Behalf Of fkolmann@revlon.com.au
Sent: Friday, February 11, 2000 1:05 AM
To: RPG400-L@midrange.com
Subject: CHAIN or READ without lock


Thought I would check if others have experience something like this.

The CHAIN or READ without lock is a new function (well sort of) , but do
you know it also READS LOCKED records.

We had duplicate invoice numbers in our order processing application.
It was caused by  the 'N'  (no lock ) on a CHAIN op.
I checked the manual and if you read the fine print, yes  you can read a
LOCKED record with
a CHAIN or READ  even if the file is opened for UPDATE, provided you use
a N to request a
read without lock.
Personally I stay away from the read without lock.


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