Query to find all the newly installed SMS client machines since 30 days

select a.Netbios_Name0,a.resourceid,a.Client0,a.Active0,a.Obsolete0,a.Creation_date0,
c.sms_Assigned_sites0 as 'sitecode',d.Lasthwscan
from v_r_system a
left outer join v_RA_System_SMSAssignedSites c on a.resourceid=c.resourceid
left outer join v_GS_WORKSTATION_STATUS d on a.resourceid=d.resourceid
where DATEDIFF (dd,a.Creation_date0,GetDate())<30
order by a.Creation_date0 desc

Description:

This query lists all the newly installed SMS client machines for the last 30 days with their assigned site code and last hardware scan date.