We are scheduled to add two new nodes. I was asked about PPIs and valued ordered indexes on tables. 1. why is this important? 2. Where can I find material about merging nodes? 3. Are there any other considerations that I need to be aware of?
Adding nodes should be relatively painless and transparent to your applications. The Teradata servers are designed from the ground up to be easily expandable. All the details of integrating the new nodes will be handled by the Teradata field engineer at installation time.
I assume you are also adding disks along with the new nodes. If so, the field engineer will run a data reconfiguration program after installing the hardware; this redistributes the rows in all of the existing tables evenly across the old and new nodes.
I am not aware of any special considerations for PPI or value-ordered indexes.