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Date:	Mon, 21 Sep 1998 13:52:07 PDT
From:	Steven Levine <steve53@earthlink.net >
Reply-To:	scoug-programming@scoug.com
To:	scoug-programming@scoug.com
Subject:	SCOUG-Programming: Need help selec

In , on 09/21/98
at 10:11 AM, MDINET!ELMONTE!TomE@mdipo.attmail.com (Emerson, Tom #
GPS-MDI) said:

>What do they mean by "not network aware"? Nowadays, I would think that
> would translate to "not multi-process aware" since you should be able to
> "export" the directory containing the database for access by other
>workstations, the program running on the other workstation should "think"
> that the data base is on a local drive. From the point of view of the
> workstation containing the database, someone accessing the data "from
>the network" should appear as simply another process reading a
>(shared) file.
> Someone accessing a file on your system while you are accessing it
>locally should look no different (to your system) than two processes on
> your own system running concurrently.

This is somewhat true. These days "network aware" usually implies
client-server. The personal edition may only support one process
accessing the database at any time, dunno. DB/2, like it's peers, is true
client-server. The clients have no direct access to the DB. All requests
go to the servers (yes there may be multiple instanaces). "Network aware"
in this case means that the client "knows" how to connect to a server over
the network.

I could go on a bit about locking. Let's just say that file locking is
best avoided when dealing with databases. Locking is done at the record
level and with as few restrictions as possible. Otherwise performance
goes in the tank.

Steven

--
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Steven Levine MR2/ICE #10183
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