转换行允许重复

Question

考虑下面的表和行列：

上市A.

ID, name, event, type 
1, 'John Doe', '2010-09-01 15:00:00.000', 'input' 
1, 'John Doe', '2010-09-03 11:00:00.000', 'input' 
1, 'John Doe', '2010-09-04 17:00:00.000', 'input' 
1, 'John Doe', '2010-09-02 15:00:00.000', 'output' 
1, 'John Doe', '2010-09-03 16:00:00.000', 'output' 
1, 'John Doe', '2010-09-06 17:00:00.000', 'output' 

我想要的是将行转换成列，所以我可以有两个不同的列，输入事件并输出事件。像：

上市B.

ID, name, input event, output event 
1, 'John Doe', '2010-09-01 15:00:00.000', '2010-09-02 15:00:00.000' 
1, 'John Doe', '2010-09-03 11:00:00.000', '2010-09-03 16:00:00.000' 
1, 'John Doe', '2010-09-04 17:00:00.000', '2010-09-06 17:00:00.000' 

我能得到类似如下：

清单C.

ID, name, input event, output event 
1, 'John Doe', '2010-09-01 15:00:00.000', null 
1, 'John Doe', '2010-09-03 11:00:00.000', null 
1, 'John Doe', '2010-09-04 17:00:00.000', null 
1, 'John Doe', null, '2010-09-02 15:00:00.000' 
1, 'John Doe', null, '2010-09-03 16:00:00.000' 
1, 'John Doe', null, '2010-09-06 17:00:00.000' 

，但问题是如何平行，因为重复元组的ID-name是相关的。要转换行到列我通常这样的代码的东西：

select ID, name, max(case when type = 'input' then event else null end) as 'input event', max(case when type = 'output' then event else null end) as 'output event' from events group by ID, name 

，但当然，本集团将要离开了重复，这就是我不想要什么。

任何想法如何实现与查询？

这将是一个便携式SQL解决方案或postgresql，但任何想法非常感谢，很高兴。

编辑：抱歉，迟到的答案。 AlexRednic和Mark Ba​​nnister的解决方案都能达到我想要的效果。我终于选择了第二个，因为它对我来说更加清晰。谢谢你的回答！

Answer 1

尝试以下操作：

select ID, name, event as 'input event', 
     (select min(o.event) 
     from events o 
     where o.type = 'output' and 
       i.ID = o.ID and 
       i.name = o.name and 
       i.event < o.event) as 'output event' 
from events i 
where i.type = 'input' 
group by ID, name, event 

Answer 2

我从一开始就写着：

create table #a(
ID int, 
name varchar(30), 
event datetime, 
type varchar(10) 
) 

insert #a 
select 
1, 'John Doe', '2010-09-01 15:00:00.000', 'input' 
union select 1, 'John Doe', '2010-09-01 16:00:00.000', 'input' 
union select 1, 'John Doe', '2010-09-01 17:00:00.000', 'input' 
union select 1, 'John Doe', '2010-09-02 15:00:00.000', 'output' 
union select 1, 'John Doe', '2010-09-02 16:00:00.000', 'output' 
union select 1, 'John Doe', '2010-09-02 17:00:00.000', 'output' 

- 这里是解决方案SQL

select 
    ID, 
    name, 
    case when type = 'input' then event else null end "input event", 
    case when type = 'output' then event else null end "output event" 
from #a 

Answer 3

select t1.id,t1.name,t1.event,t2.event from test t1 
    inner join test t2 on t1.event <= t2.event 
     and t1.type = 'input' 
     and t2.type = 'output' 
        and t1.id = t2.id 
        and t1.name = t2.name 

是你需要以某种方式输入链接的事/输出会话。在这个查询中，我通过使用时间戳事件列来完成它。如果这不是你想要的，你能提供更多的信息吗？

更新：现在，到后处理了一下，你可以做

with a as 
(
select t1.id,t1.name,t1.event as in_event,t2.event as out_event from test t1 
    inner join test t2 on t1.event <= t2.event 
        and t1.type = 'input' 
        and t2.type = 'output' 
        and t1.id = t2.id 
        and t1.name = t2.name 
) 
select id,name,in_event,min(out_event) 
     from a 
group by id,name,in_event