Question

我正试图在佛蒙特州和纽约州的会员生日表中找到最年长的人。我的会员类似于以下内容：

Members
-------
MemberID, Firstname, Lastname, Birthday, Region

我制定了以下子查询：

SELECT lastname 
FROM members 
WHERE region = 'VT' 
  AND year(birthday) > (SELECT year(birthday) 
                        FROM members 
                        WHERE region = 'NY')

SQL查询系统告诉我它返回多行。我错过了什么，它在逻辑上是否正确？我再问一遍，我怎么能找到佛蒙特州的每个成员都比纽约的所有成员都年长。

Answer 1

   select top 1 * from table where region='vermont' or region ='newyork' order by year(birthday) desc

Answer 2

您需要找到NY成员的最大生日，这样您才能获得一个值。然后使用该值查找大于NY

最大值的VT成员

你可以试试这个：

select lastname 
from members where region = 'VT' and year(birthday) >
(select max(birthday) from members where region = 'NY')

逻辑运算符>要求运算符右侧只有1个值。

Answer 3

做的：

select lastname from members where region = 'VT' and year(birthday) 
>
(select year(birthday) from members where region = 'NY' ORDER BY birthday ASC LIMIT 1)

Answer 4

我没有得到大部分答案。它们没有涉及纽约和纽约。 VT要求（除了重现模棱两可的问题vs“我试过的”）。更小生日的人也一定年纪越大。

SELECT lastname 
FROM members 
WHERE region in('VT' ,'NY') and birthday = 
(SELECT MIN(birthday) 
FROM members where
region in('VT' ,'NY') )

生日表中最老的人。 SQL子查询

4 个答案: