Data Guard

[nik_flash]

Hi
Can somebody tell me the disadvantages of using Data guard?
We want to have a replica of Production system which we can use for reporting purpose. But I dont want it to have any impact on the production system. So are there any performance issues linked with it which can affect the production system's performance also?

[fraze]

We use Dataguard on the majority of our production systems and it hasnt given us any performance issues on any of them. What you do have to watch out for though is the speed you can copy over the redo logs to the standby side - if your system is generating a lot of redo your network/applying of the logs may not be able to keep up.

[nik_flash]

Originally posted by fraze
We use Dataguard on the majority of our production systems and it hasnt given us any performance issues on any of them. What you do have to watch out for though is the speed you can copy over the redo logs to the standby side - if your system is generating a lot of redo your network/applying of the logs may not be able to keep up.

Thanx a lot for the reply fraze
I have one more doubt on Data Guard
I want to use data from the replicated database (Physical standby replicated database by data guard method) in a new system which will have its own database and the tables in that database needs data from the replicated database. Is it possible to have a different schema in the replicated database where I can put this new system's database objects and access data from the replicated database using synonyms.
One more question is it possible to have other objects in the replicated database apart from the readonly (replicated objects).i.e Can I create new objects in the replicated database which are not read only.

[jrpm]

If you are using replication rather than a standby database, then the receiving database can have it's own objects, I believe (I am not our replication specialist, but I think that is how one of our configurations is set up, based on replication groups.)

If you are using a standby database (as implied by the mention of log shipping), then no. I believe the database must be a clone. It might be available in READ ONLY mode (for reporting), but is must be a clone of the data structures and contents.

[nik_flash]

Originally posted by jrpm
If you are using replication rather than a standby database, then the receiving database can have it's own objects, I believe (I am not our replication specialist, but I think that is how one of our configurations is set up, based on replication groups.)

If you are using a standby database (as implied by the mention of log shipping), then no. I believe the database must be a clone. It might be available in READ ONLY mode (for reporting), but is must be a clone of the data structures and contents.

Thanx for the answer jrpm
Can anybody give me a good approach for replication. Since I need only 30-40 Tables from the Production database but the only thing is that it has to be almost a real time or max a delay of 10 minutes replication. If I can replicated those tables in my database I need not take the full replication or a standby approach in Oracle 9i Data Guard and can create my own objects in that schema. But this needs to be done without affecting Production system's load this is important.Pls suggest

[fraze]

We use Advanced Replication for around the same number of tables in a master-master environment. We also looked at Oracle Streams but decided against it as its new technology. Probably best if you look at the Advanced Replication and Streams concept manuals on OTN to better understand them

[nik_flash]

Originally posted by fraze
We use Advanced Replication for around the same number of tables in a master-master environment. We also looked at Oracle Streams but decided against it as its new technology. Probably best if you look at the Advanced Replication and Streams concept manuals on OTN to better understand them

Thanx a lot, will check it out.