Re: Database Sync doubt

Hi,

Thanks for the response.

> Praveen, your possible solutions depend on some information not
> posted. Most importantly how current must each database be? And if
> database A is down should database B and C be available for update or
> unavailable till A is available again?

Yes in case database A is down, B and C will be available. Can it possible like if A is available again, then update A database with missing data from B and C. Is there any facility in Oracle?  

> If the data must be always in sync then placing a trigger on each
> table to update the remote instances at the time of DML activity using
> distribued transactions is one possibility. But if one database is
> down the entire system is down.

Will it be database operation will slower if, for each DML activity by trigger on each and update the remote instances?

> You could use a transaction buffering system to hold local activicy
> during remote outages and send it when the remote system become
> available.

Is this transaction buffering system is a facility/feature available in Oracle?  

> You can also look into master to master (advanced) replication.
>
> If some delays in data transmission are acceptable then Oracle's basic
> replication might be a possiblity as part of the solution.

Cient have WAN connection for their data transmission. In that case also there will be big delay in transmission?

is the oracle database replication is best option for this type of scenarios?

Thanks,
Praveen

Mark.Powell_at_eds.com (Mark D Powell) wrote in message news:<2687bb95.0410140543.6dff3828_at_posting.google.com>...
> spraveen2001_at_yahoo.com (Praveen) wrote in message news:<98d8ec76.0410132156.3e39ff9b_at_posting.google.com>...
> > Hi All,
> >
> > We are developing a billing system project. for which front-end is
> > java and backend we are using 10G. Initially we have to deploy the
> > application in two different places. Apart from these 2 places, there
> > will be one central database also. In All the three places, the same
> > application is same and database also same. Now, We wanted to sync the
> > data between these three database in three different places. Means, at
> > any point of time, all three database should have the same data.
> >
> > Can anyone please tell how should i approach to this data sync with
> > three database?
> >
> > Thanks,
> > Praveen
>
> Praveen, your possible solutions depend on some information not
> posted. Most importantly how current must each database be? And if
> database A is down should database B and C be available for update or
> unavailable till A is available again?
>
> If the data must be always in sync then placing a trigger on each
> table to update the remote instances at the time of DML activity using
> distribued transactions is one possibility. But if one database is
> down the entire system is down.
>
> You could use a transaction buffering system to hold local activicy
> during remote outages and send it when the remote system become
> available.
>
> You can also look into master to master (advanced) replication.
>
> If some delays in data transmission are acceptable then Oracle's basic
> replication might be a possiblity as part of the solution.
>
> HTH -- Mark D Powell --
Received on Thu Oct 14 2004 - 23:57:59 CDT