Two different questions (kind of).
1- The adapter instances with the same name. Why would you do that to someone? OK - on the backend the adapter instance get different identifying IDs, with the 'pretty' user description being 'the same', however you're going to confuse people when they look at the data sources for resources. Don't do it.
2 - A resource is imported in to vC Ops, and is created with unique identifying field.. think of multiple primary keys. The Unique Primary Key field are the resource NAME, and the identifierKey and identifierValue field. If this data is the same, vC Ops will think you're talking about the same resource and will MERGE the data together under the same resource. We do this with Generic SQL adapters, if you need to pull data from multiple sources, perhaps using different SQL queries, and you need to merge all of this data down to a single resource. Play with this some more and you'll see the possibilities!
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