another set of questions

Hi,

another set of questions.. please help me in this regard

1. Is there a way to undeploy the SDA that is being deployed by NWDI across the landscape. i.e. i created an activity, so an SDA/ SCA will be created and deployed in dev, test and prod. but now I want to rollback the changes that I made with that particular activity.

2. When would external library DC come into picture?

Please help me in this regard.

Thank you