--Dotted Solutions for Section 4.3, Informix
--[4.4] (a)
select e.dependents from employees e
       where cardinality(e.dependents) = 1;

--(c) 
select count(*) from phonebook pb
         where 100 in pb.extensions;

--[4.5]   (a)     Oracle or Informix: 
select eid from employees e where e.fname in
        (select t.fname from table(e.dependents) t);

--(c)
select d from table 
        (select e.dependents from employees e where e.eid =100) d 
              where d.age = 
                 (select max(age) from table (select e.dependents from
                          employees e where e.eid = 100));
select pb.phperson.ssno from phonebook pb
        where exists (select * from table(pb.extensions)
            as x(ext) --column name ext added here
        where x.ext between 800 and 900);
