Re: RMAN duplicate only used blocks?

From: Vishal Gupta <>
Date: Tue, 28 Jun 2011 17:15:16 +0100
Message-Id: <>

This is my understanding as well. RMAN will decompress the unused blocks and create an block for block copy on target database. I have not read/heard of RMAN being able to restore only used block.

Vishal Gupta
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On 28 Jun 2011, at 17:10, Allen, Brandon wrote:

> Iíve never heard of such a feature, but would also be interested to hear if someone else knows about it. Iím guessing maybe the person that mentioned this to you was just confused about the fact that RMAN will only write used blocks to the backup set, but when it restores the backup, it fills in those unused blocks again. Iím pretty sure that duplicate works exactly the same as a regular restore Ė it just automates the other stuff for you like creating the controlfile, renaming datafiles, setting the new DBID, etc. I agree that it sounds like youíll need to use data pump, unless maybe there is only a subset of tablespaces that you need Ė then you could use transportable tablespaces just for those, and you can use RMAN to create the transportable tablespaces if required to avoid downtime in the source database.
> Regards,
> Brandon
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Received on Tue Jun 28 2011 - 11:15:16 CDT

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