Hi Andrew,
I can see this being possible, however it's a little problematic.
Primarily, the issue is that transactions are asynchronous between replication
processes. DDL and DML do not exist in their own vacuum. They are often
reliant upon one another which means they need to happen in the correct order.
Think about scenarios such as application upgrades when DDL and DML could
happen at similar times. Inserts on tables (with extra or missing columns).
Your DDL would get replicated from your primary environment, let's say dropping
a column, before the data gets applied at the standby, extracted, and sent
through GG to your replicat. Inserts or updates on these rows would abend as
the table definitions aren't the same. You may be able to handle some
scenarios through complex CDR rules, however I can't see it working cleanly all
the time.
Why are you not wanting to replicate everything from the primary? If it's
resource constraints you may look into using a downstream mining database.
It does not house any data, It simply houses the logminer processes which are
responsible for extracting trails from your primary servers archive logs.
To be brutally honest, I think goldengate is an administration nightmare
before adding in this hickup. I've found anything you can do to simplify the
environment at the start will pay off 10x in the future.
Thanks,
Ryan
On Apr 17, 2015, at 12:35 PM, Andrew Kerber <andrew.kerber@xxxxxxxxx> wrote:
Well, I didn't get many answers to my question about GoldenGate training, so
I suspect its not used a lot. But anyway, I have been setting up a proof of
concept configuration, and I have managed to get schema level replication
going. I think I have DML from a dataguard physical standby figured out, but
according to the documentation, I cannot replicate DDL from a standby
database.
Can someone give me some pointers about replicating only DDL from the primary
of a dataguard physical standby configuration? I will replicate DML from the
standby, so I only want to replicate DDL from the primary.
--
Andrew W. Kerber
'If at first you dont succeed, dont take up skydiving.'
