Hello Roberto,
As in DMC V3.1.11, and DMC V3.1.12 we did not have a significant amount of changes or new features in the product since DMC V3.1.10, we decided to not update the User's Guide at this time.
You can still refer to the DMC What's New chapter in the DMC manual to see the changes for each version here: https://www.ibm.com/docs/en/db2-data-mgr-console/3.1.x?topic=console-whats-new
I hope that helps!
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Cintia Ogura
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