Something like this?
select distinct a.ordernumber
from tblorder a
where a.ordernumber not in
(select distinct b.ordernumber
from tblorder b
where right(b.itemnumber,3) 'rtd')
The absence of evidence is not evidence of absence
- Martin Rees
The absence of consumable DDL, sample data and desired results is, however, evidence of the absence of my response
- Phil Parkin