1)alter table orders
alter column received
datetime not null
2)alter table orders
constraint shipped1 unique(shipped)
constraint shipped2 check(shipped = “” or shipped > received)
10.
1) select pno
from part
where unitprice > 10 and unitprice <25
2) select ono,qty,billedprice
from invoice
where ono in (select ono
from orders
where received like "%1998")
compute sum(qty)
order by billedprice asc
3) select ono,pno,qty,billedprice
from invoice
where ono not in (select ono
from orders
