SQL将多行合并为多列

Question

我的查询结果中有多行：

例如，表“地址”：

Street | Number | City
----------------------
A1     | A2     | A3
B1     | B2     | B3

我真正想要的是：

Address1_Street | Address1_Number | Address1_City | Address2_Street | Address2_Number | Address2_City
------------------------------------------------------------------------------------------------------
A1              | A2              | A3            | B1              | B2              | B3

谁知道我能做到这一点吗？

我现在已经设法解决了这一点（很抱歉使用其他列，上面的只是一个例子，但是我想您会明白的）：

select distinct
    a.ID,
    a.Name, 
    ca1.NameLine1 as Address1_NameLine1, 
    ca2.NameLine1 as Address2_NameLine1
from 
    dbo.Accounts a, 
    dbo.Addresses ca1,
    dbo.Addresses ca2
where 
        (a.ID = ca1.AccountID AND a.ID = ca2.AccountID)
    AND (a.Name = 'TEST')
    AND (ca1.ID <> ca2.ID)

但是我仍然得到2行...其中Address1与Address2切换。 谁知道只会得到一个吗？ 谢谢！

Answer 1

尝试：

select ID,
       max(Name) Name,
       max(case when rn=1 then NameLine1 end) Address1_NameLine1,
       max(case when rn=2 then NameLine1 end) Address1_NameLine2
from
(select a.ID,
        a.Name, 
        ca.NameLine1,
        rank() over (partition by a.ID order by ca.ID) rn
 from dbo.Accounts a 
 join dbo.Addresses ca on a.ID = ca.AccountID
 where a.Name = 'TEST') sq
group by ID

Answer 2

select address1.* ,address2.* from
Address address1 inner join on Address address2
on address1.userid=address2.userid

您可以根据数据选择内部联接或左联接。