Re: Question on asynchronous data propagation from a local to the central oracle database

In article <WyvU8.26378$Hj3.81724_at_newsfeeds.bigpond.com>, "Richard says...
>
>Hi Bhooshan,
>
>No it's not. You can always manually configure the required links and use
>the various packages (DBMS_REPCAT_ADMIN, DBMS_REPCAT, DBMS_DEFER_SYS,
>DBMS_JOB, etc, etc) to setup and control your replicated environment.
>
>That said, the GUI tool is a lot easier to use (in my technically deficient
>opinion).

Agreed, though sometimes you can only diagnose a problem by using the packages directly.

>
>Cheers
>
>Richard
>"Bhooshan Prabhu" <bhooshan.s.prabhu_at_orbitech.co.in> wrote in message
>news:16584988.0207022050.7106988e_at_posting.google.com...
>> Thanks Pete,
>>
>> One more doubt. Is it an absolute must to use the Oralce replication
>> manager tool to configure the replication environment, replication
>> groups, objects etc.
>>
>> Regards
>> Bhooshan
>>
>> Pete Sharman <peter.sharman_at_oracle.com> wrote in message
>news:<afsor002l7k_at_drn.newsguy.com>...
>> > In article <16584988.0207020053.5219e6f7_at_posting.google.com>,
>> > bhooshan.s.prabhu_at_orbitech.co.in says...
>> > >
>> > >Hello,
>> > >
>> > >I am in the process of evaluating various methods for propagating data
>> > >from a local Oracle database to a central Oracle database. Oracle
>> > >version is yet undecided but it would either be Oracle 8.1.7 (I know
>> > >it gets desupported by December 2003) or Oracle 9i on Solaris m/c.
>> > >
>> > >The local database that I refer to, would be a database located in
>> > >offices located at geographical locations that offer poor
>> > >infrastructure and network bandwidths. The number of local databases
>> > >could be up to 150-200.
>> > >
>> > >The central database shall be 1 and shall be used by users from
>> > >offices that are in developed countries that offer good network
>> > >bandwidths. Thus, both the central as well as the local database can
>> > >be in use by different set of users at the same time.
>> > >
>> > >The users would be accessing both these databases over web based
>> > >applications.
>> > >
>> > >The requirement is that the data that gets added / modified / deleted
>> > >at the local database site should be propagated to the central
>> > >database but, in an asynchronous mode.
>> > >
>> > >I have read about data replication methods provided by Oracle. I've
>> > >the following queries.
>> > >1. Would it be possible to replicate data off a table from a local
>> > >database to
>> > > the central database while the table at the central database itself
>> > >might be
>> > > getting its own data from users? i.e. Table A is being inserted
>> > >into in the
>> > > local database at site A. Oracle replication shall try and
>> > >propagate the
>> > > insert to central site C. At that moment, a user B might be
>> > >inserting data
>> > > in the table A at central site as well. Would replication work when
>> > >the table
>> > > at the master site would also be active? I guess yes but, need
>> > >confirmation
>> > > from some one..
>> >
>> > Yes. Otherwise multi-master replication or master-updatable snapshot
>> > replication would not work.
>> >
>> > >
>> > >2. The data from the local database needs to be available at the
>> > >central site
>> > > in near real-time but, not real-time. I gather that the jobs to
>> > >replicate
>> > > data from the local to the central database shall get executed at a
>> > >certain
>> > > frequency. Can this frequency be set to 1 minute? Is anyone aware
>> > >of any
>> > > repercussions if the frequency is kept so low?
>> >
>> > I tend to not go below 5 minutes because then the overhead of checking
>whether
>> > there are rows to move or not MAY cause a performance issue. Note the
>MAY is in
>> > uppercase because you can't confirm this till you do quite a bit of
>testing.
>> > However, near real-time may not be possible for you anyway if there are
>network
>> > problems like you stated earlier.
>> >
>> > >
>> > >3. I can also think of Oracle advanced queues as another Oracle
>> > >technology
>> > > offering that could prove useful to carry out the data propagation
>> > >from the
>> > > local to the central site. How reliable is Oracle AQ in terms of
>> > >stability,
>> > > robustness and maintainability?
>> >
>> > Replication uses the AQ technology anyway.
>> >
>> > >
>> > >4. The application shall be developed using Java and shall get
>> > >deployed at both
>> > > the central as well as the local sites either using a Web server or
>> > >Apps
>> > > server. EJB 2.0 specifications do specify message driven beans. I
>> > >feel that
>> > > the data propagation can also be carried out using JMS and the
>> > >message
>> > > driven beans. Any feedback on this thought?
>> >
>> > Never tried this apporach so I can't comment.
>> >
>> > >
>> > >Regards
>> > >Bhooshan
>> >
>> > HTH. Additions and corrections welcome.
>> >
>> > Pete
>> >
>> > SELECT standard_disclaimer, witty_remark FROM company_requirements;
>
>

HTH. Additions and corrections welcome.

Pete

SELECT standard_disclaimer, witty_remark FROM company_requirements; Received on Wed Jul 03 2002 - 11:25:37 CDT