在Oracle中，我们可以在这里使用keep语法：

select last_name,
    min(first_name) keep(dense_rank first order by length(first_name)) shortest_last_name,
    min(first_name) keep(dense_rank last  order by length(first_name)) longest_last_name
from employees
group by last_name;

如果存在最短或最长名字的关系，则查询按字符串方式选择“最小”值。
下面是一个demo：

with employees as (
    select 'Mickey' as last_name, 'Max' as first_name from dual
    union all select 'Mickey', 'Ronald' from dual
    union all select 'Mickey', 'Bill' from dual
    union all select 'Duck', 'Bob' from dual
    union all select 'Duck', 'Howard' from dual
    union all select 'Bob', 'Max' from dual
    union all select 'Bob', 'Howard' from dual
)
select last_name,
    min(first_name) keep(dense_rank first order by length(first_name)) shortest_last_name,
    min(first_name) keep(dense_rank last  order by length(first_name)) longest_last_name
from employees
group by last_name;

fiddle