Question

Consider table A:

Status                Person
------                ------
Married               Andy
Married               Bob
Married               Carol
Has Kids              Bob
Has Kids              Carol

Consider table B:

Married & Has Kids    Bob
Married & Has Kids    Carol

我可以得到表A，我可以得到表B，但是如何一起显示A和B？我是SQL的新手，所以我对UNION有一个模糊的想法，那会是最好的方法吗？

编辑：

所以，我有点撒了谎。我无法准确得到表B，但类似：

Married               Bob
Has Kids              Bob
Married               Carol
Has Kids              Carol

我正在使用SQL Server 2012.这是我对表A的查询：

SELECT Status,Person
FROM Records
WHERE Status IN ('Married', 'Has Kids')
GROUP BY Status,Person
ORDER BY Status,Person

查询表B-ish：

SELECT Status,Person
FROM Records
WHERE Status='Married' AND Status='Has Kids'
GROUP BY Status,Person
ORDER BY Status,Person

我想要这样的表：

Status                Person
------                ------
Married               Andy
Married               Bob
Married               Carol
Has Kids              Bob
Has Kids              Carol
Married & Has Kids    Bob
Married & Has Kids    Carol

Answer 1

一种方法是使用自联接并将状态连接在一起：

select status, person from a
union all
select concat(married.status, ' & ', kids.status) status, kids.person
from a kids 
join a married on kids.Person = married.Person
where kids.Status = 'Has Kids' and married.Status = 'Married'

这将为您提供示例中的确切输出。

Sample SQL Fiddle

或者您可以按照建议使用for xml path的相关子查询：

SELECT Status, Person FROM A 
UNION ALL
SELECT Status = LTRIM(STUFF((
          SELECT '& ' + a.Status
          FROM a 
          WHERE a.Person = a1.Person
          FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 1, ''))
        , person 
FROM A A1 GROUP BY Person HAVING COUNT(Status) = 2

合并分组列的结果

1 个答案: