1. A view in SQL is defined using the create view command:

create view v as (query expression)

where (query expression) is any legal query expression. The view created is given the name v.

2. To create a view all-customer of all branches and their customers:

create view all-customer as
(select bname, cname
from depositor, account
where depositor.account# = account.account#)
union
(select bname, cname
from borrower, loan
where borrower.loan# = loan.loan#)

3. Having de ned a view, we can now use it to refer to the virtual relation it creates. View names can appear
anywhere a relation name can.

4. We can now nd all customers of the SFU branch by writing

select cname
from all-customer
where bname="SFU"