[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Merging Ozone databases



Falko Braeutigam wrote:

> On Wed, 25 Jul 2001, you wrote:
> > Writing a quick hack on top of your existing Java code that talks to the
> > database would sound like the best bet. Have it load in from the two to be
> > merged and write to a third instance (that way you can experiment on how to
> > prevent collisions in your particular case).
>
> Yes, 'collisions' are the problem. If your objects do not form two fully
> separated graphs, then merging 'by hand' is the only way doing it. Only the
> the application logic (inside the objects and/or inside the client code) knows
> what are valid object struktures and how to build them.
>
> Roy, why do you want to merge the databases?

We have large amounts of geographic data that we need to import fast.  This is a slow
process because of the nature of geographic data - the data and the graph is usually
more complex than traditional business application data.  We want to take a look at
using a distributed setting - different machines processing smaller portions of a
larger whole - then bring the pieces together into one database repository.  We hope
to reduce import time from 30 days to maybe 3 days in one case.  This isn't a one time
deal.  We need to re-import that original data when it is updated.  We also have to
import large amounts of other new data on a regular basis (such as Naval ocean survey
data).


> How does the object structure
> look like?

The databases are two fully separated graphs.  However, each graph contains rather
complex inter-relationships among objects.


> Do the two databases have different db IDs? (otherwise object IDs
> may collide)

Object ID collision is a big concern.  Is there a way that I can ensure that the two
databases will have different db IDs?  Is there a convenient way to update IDs as I
merge without creating new objects in the merged database?


>
>
> Falko
>
> >
> > Reason
> > http://www.exratio.com/
> >
> > > -----Original Message-----
> > > From: owner-ozone-users@ozone-db.org
> > > [mailto:owner-ozone-users@ozone-db.org]On Behalf Of Roy Ladner
> > > Sent: Wednesday, July 25, 2001 12:55 PM
> > > To: ozone-users@ozone-db.org
> > > Subject: Merging Ozone databases
> > >
> > >
> > > I have 2 Ozone databases and I want  to merge them into one database
> > > without re-importing the raw data from data files.
> > >
> > > Can anyone give their experience with this or some insight into doing
> > > this efficiently?
> > >
> > > Roy Ladner
> > > Naval Research Laboratory
> > >
> > > ----------------------------------------------------------------------
> > > Post a message:         mailto:ozone-users@ozone-db.org
> > > Unsubscribe:
> > > mailto:ozone-users-request@ozone-db.org?body=unsubscribe
> > > Contact adminstrator:   mailto:ozone-users-owner@ozone-db.org
> > > Read archived messages: http://www.ozone-db.org/
> > > ----------------------------------------------------------------------
> >
> > ----------------------------------------------------------------------
> > Post a message:         mailto:ozone-users@ozone-db.org
> > Unsubscribe:            mailto:ozone-users-request@ozone-db.org?body=unsubscribe
> > Contact adminstrator:   mailto:ozone-users-owner@ozone-db.org
> > Read archived messages: http://www.ozone-db.org/
> > ----------------------------------------------------------------------
> --
> ______________________________________________________________________
> Falko Braeutigam                              mailto:falko@smb-tec.com
> SMB GmbH                                        http://www.smb-tec.com
>
> ----------------------------------------------------------------------
> Post a message:         mailto:ozone-users@ozone-db.org
> Unsubscribe:            mailto:ozone-users-request@ozone-db.org?body=unsubscribe
> Contact adminstrator:   mailto:ozone-users-owner@ozone-db.org
> Read archived messages: http://www.ozone-db.org/
> ----------------------------------------------------------------------

----------------------------------------------------------------------
Post a message:         mailto:ozone-users@ozone-db.org
Unsubscribe:            mailto:ozone-users-request@ozone-db.org?body=unsubscribe
Contact adminstrator:   mailto:ozone-users-owner@ozone-db.org
Read archived messages: http://www.ozone-db.org/
----------------------------------------------------------------------