I have a couple of fields, Node and NodeID, which will both have a number. Then I have NodeName which is of the format "Node001", so to make sure they all have a NodeName, I did this
eval NodeName="Node".substr("000".NodeId,-3) | eval NodeName = "Node".substr("000".Node,-3)
However, this seems rather wasteful. How would I combine this into one statement? It's unlikely an event will have both Node and NodeID, but I'd have to dig through the data more
Try this
.... | eval NodeName="Node".substr("000", coalesce(NodeId, Node), -3)