Query workbench DP(1.1) Results of query execution on index node are still correct even if the data node goes down

1.Create a 4 node cluster out of which only 1 is data,index and query node.Rest are all index node.
2. Launch the query workbench script on any of the index nodes.( Example: http://172.23.106.40:8091/index.html#sec=servers)
3. Failover rest of the nodes except the query UI node which is the index node.
4. Query execution UI still works properly.

I am not sure what should be the ideal state/message reported on the query UI.
But the state of couchbase console in attached.