id field is primary key w/1 increment identity on that field as well.

I can do:
select * from trnhead where shipped=0 order by id
fine.

but:
select * from trnhead where shipped=0 order by id
union all
select * from ordhead where shipped=0 order by id
won't work with the order bys in there.

I just took the order bys out since the ordering is okay it seems without, but:

Does anyone know why?