Queries against the bank database

1. Show amount loaned by each branch

 select branch.branchName,sum(balance) from loan natural join branch group by branch.branchName;

2. Natural join example


 select * from loan natural join branch;

3. Left outer join example

     select * from loan natural left outer join borrower;

Left outer join example with using condition
  select * from loan  left  join borrower using (loanNumber);

4. Right outer join example


  select * from loan natural right outer join borrower;

5.  Full outer join


6. What does this do ?

 select * from loan foo join borrower;


7. Show customer names and number of loans held by each customer

 select customer.customerName,count(*) from
     -> customer natural join borrower
     -> group by customer.customerName;

8. (select * from borrower) union (select * from depositor); // union


9. insert into emp(field1)
    -> (select ename from employees); // inserting result of a query