Re: Logical Standby Database 10gR2

On 25 Apr 2007 08:13:44 -0700, tinojam <tinojam_at_gmail.com> wrote:

>We are designing a DR plan for our production database which is a
>Oracle10gR2 RAC database with three nodes in the cluster. Based on our
>business requirements and cost constraints we have decided to build a
>logical standby RAC database (3 nodes) at our remote site. The
>business wants to use the standby database as a DR database and for
>reporting, 24X7. That is why I went the logical standby route. I have
>done the ground work in terms of checking that there are no
>unsupported data types for the logical standby db and everything
>checks out.
>
>Now the problem is this: the DBA team went to a presentation and an
>Oracle representative told them that they need a physical standby and
>a logical standby database to ensure the logical standby database
>works. He is saying that he wouldn't recommend having a logical
>standby db by itself, you need a physical standby database, based on
>best practices.
>
>Now the DBAs want the design to be changed to accommodate both a
>logical and physical standby database... extra cost and
>administration!
>
>Is there anyone out there just using a logical standby database for
>both reporting and DR without a physical standby?
>
>I have been working with standby databases since Oracle8i and I am
>sure the design is up to par. I want to get feedback from the group on
>this...

I would recommend reading the documentation on logical standby databases carefully. Not all datatypes are logical standby compatible. Tables with columns in those datatypes will be suppressed automagically.
Consequently you can't and shouldn't use a logical standby as a disaster recovery mechanism.

-- 

Sybrand Bakker
Senior Oracle DBA