If you mean the most recent activity for a device talking to LANDesk, the best you'll be able to work with is likely:
"Computer"."Last Updated by Inventory Server"
If you just want a list of every device's date in this field, just put this field in the output columns,
and then query for:
"Computer"."Device ID" exists
This will almost always produce a list of EVERY device in the database, and with the date field above as the output, you'll get a nice list.
You might want to include the other dates as output as well for comparisons, but most of the time the "Last Updated by Inventory Server"
is usually always the most up to date value.
Hope that's what you're looking for.