Below query that will show the Assets that has a scan status.
select systeminfo.workstationname "Workstation Name",
LONGTODATE(audithistory.audittime) "Last Scanned on",
audithistory.auditstatus "Scan status"
from audithistory
left join systeminfo on systeminfo.workstationid=audithistory.workstationid
where audithistory.auditid in (Select max(audithistory.auditid) from audithistory group by workstationid)
Below query shows only failed scan status.
select systeminfo.workstationname "Workstation Name",
LONGTODATE(audithistory.audittime) "Last Scanned on",
audithistory.auditstatus "Scan status"
from audithistory
left join systeminfo on systeminfo.workstationid=audithistory.workstationid
where audithistory.auditstatus!='SUCCESS'
and audithistory.auditid in (Select max(audithistory.auditid) from audithistory group by workstationid)