RE: update in single page subfile

["Reeve Fritchman" <reeve@xxxxxxxxxx>]

Commitment control: you, the programmer, have the ability to control when a
series of database transactions (writes, deletes, updates to journaled
files) is "complete".  You execute "COMMIT" in the program when the
application has completed the "logical" transaction (which could include
thousands of database transactions); you use "ROLBK" (rollback) when you
want the system (which is why this is so cool) to undo a partially-completed
or failed transaction.  The "COMMIT" operation, even though it's used at the
completion of a transaction, is actually a starting point for keeping track
of journaled database transactions until the next COMMIT or ROLBK.

My application (transportation) can include a large number of database
transactions when a truck is dispatched: I update the 1-6 equipment master
records, add 1-6 history records, update 1-2 driver master records, add 1-2
driver history records, update 1-3 manifest records, add 1-3 manifest
history records, update 1-10,000 shipment records, and write 1-10,000
shipment history records.  If any part of this process fails (up to the last
record), a ROLBK undoes everything since the last COMMIT.  Otherwise, a
COMMIT finalizes the transaction and starts keeping track of all new
database transactions pending the next COMMIT or ROLBK.

Buck's right: you should do some reading!

-reeve

-----Original Message-----
From: rpg400-l-admin@midrange.com [mailto:rpg400-l-admin@midrange.com]On
Behalf Of Buck Calabro
Sent: Monday, October 14, 2002 2:16 PM
To: rpg400-l@midrange.com
Subject: RE: update in single page subfile

>I want to update records in subfile which
>is having thousands records(lessthan 10k)..
>reading this records is done in single
>page)...please suggest me which subfile is good
>(loadall/expand/single page)to update and

I always use expanding.  I don't use scroll bars though, which might be a
good reason to load all.

>at the same time i should lock the records without
>giving chance to others to update...how can i lock
>the records?

You really want to lock several thousand database records?  Commitment
control can do this for you, but you need to do some reading so that you
understand how it works.  There isn't an easy way to explain the details of
commitment control in an email exchange.
  --buck
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