How to show a list that compare the thing which not show up in a csv file

[phamxuantung]

So in detail, I have a dashboard that read log files to monitor the list of host's status which is UP or DOWN. But when some hosts are offline, then there would be no log file of their. I have a csv file that list out all the host name, and I want to compare the two list that I have, to have it show the offline hosts, which is the hosts name that show up in the csv file but not on the dashboard that I already have. 

[ITWhisperer · Accepted solution]

search
| dedup host
| append [| inputlookup csv | dedup host]
| stats count by host
| where count=1