Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> comp.databases.theory -> Re: Replication

Re: Replication

From: Graham Bellamy <dontwriteme_at_ask.first.com>
Date: Tue, 28 May 2002 04:49:20 +1000
Message-ID: <actuss$5fh$1@perki.connect.com.au>


>
>
> Graham Bellamy wrote:
>
> > > "Hugh O'Neill" <hugh.oneill_at_btconnect.com> wrote in message
> > > news:3CC52268.D6D6B8E1_at_btconnect.com...
> > > > Replication is for situations where users are not on the same network.
> > > Inherently, updating
> > > > with the central master will be infrequent. I don't think this is for
> > > you!
> >
> > What if a sales rep wants to be able to use the db on his laptop at home, or on the
road
> > during business hours. If I put a replica on his laptop, he could bring it back in the
> > morning and update. But when he makes a quote, my code chooses the next quote number
(PK)
> > for him, which being disconnected from the network, will at some time produce
duplicates
> > with the back end on the server. Firstly, how will this get updated to sort out the
> > duplication? Secondly, if he then uses this number for some reason, maybe in a word
> > document, then the number gets changed upon updating, this will screw his paperwork
(or
> > non-linked information) up. How do I cope with this?
> >
> > TIA
> > Graham
>
> "Hugh O'Neill" <hugh.oneill_at_btconnect.com> wrote in message
news:3CF1753D.3176F222_at_btconnect.com...
> The following ideas may be be useful and you should look at "AutoNumber fields and
replication"
> in Help so so can see what happens to Autonumber ( I'd recommend setting its 'Field
Size' to
> 'Replication ID' for this application.
>
> Autonumber will give the system a unique identifier for your 'quote' records but don't
be
> tempted to use it for the actual 'quote' number! Instead, use one of several numbering
systems
> used for document numbers. On the Salesman's machines the numeric value produced will
be unique
> on his machine.
>
> When his records are synchronised to the Office system, his 'quote' numbers may be the
same as
> other people's so you must make sure that field allows duplicates. All 'quote' records
should
> have another field containing an automatic identifier to show the Salesman or Terminal
and that
> identifier, with the above number, forms the 'quote' reference that appears on documents
and
> other reports. Again, don't be tempted to put the number and Salesman identifier into
one
> string in one field. If you do, you will almost certainly be sorry later!
>
> Remember, the records have unique identifiers given them by the Replication ID
Autonumber and
> the 'quote' number is just a piece of data in the record like a post code. Access will
use the
> Autonumber for handling internal links and you will use the 'quote' ref for the human
side of
> things.
>
> hth
>
> Hugh
>

Thanks Hugh, I'll give it some consideration. My first thoughts are that I don't like the duplication of the number part of the Quote number; I was hoping to keep them unique from quote to quote. However, I am now thinking of the situation of revisions (slight modifications) of quotes, in which it would be visually more logical to the user to duplicate the number part, and add a revision field. So if I'm going to do that, I guess adding the salesman's initials to the number is not much different.

Is it a standard practice to copy an entire record (with all it's child relations), even if the revision is to adjust one field (could be any field)? I can't think of any other practical way of doing it. Surely this blows Normalization to pieces.

Graham Received on Mon May 27 2002 - 13:49:20 CDT

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US