What are all the savings balances?
select balance from savings
What is the lowest one?
select min(balance) from savings
What is the name on the account has the lowest one?
select t1.name from accounts as t1 join savings as t2 on t1.custid = t2.custid order by t2.balance limit 1
Also provide the checking balance.
select t1.name, t2.balance from accounts as t1 join checking as t2 on t1.custid = t2.custid join savings as t3 on t1.custid = t3.custid order by t3.balance limit 1