-- (a) Report new values
select distinct property 
from #HOLD
where property not in (select property from table2)

-- (b) Mark records containing those new values
update #HOLD set record_state='N'
where property not in (select property from table2)

-- (c) Generate new dictionary items (assumes auto-incrementing ID column)
insert table2 (property)
select distinct property
from #HOLD
where property not in (select property from table2)

-- (d) Delete records containing an unknown value (assumes you didn't
--     add new dictionary items)
delete #HOLD 
where property not in (select property from table2)