Question

我正在尝试查找故障单更改所有者组的次数。我正在使用此查询：

SELECT        
TICKETID, CHANGEDATE, OWNERGROUP, 
RANK() OVER (Partition by TICKETID, OWNERGROUP ORDER BY CHANGEDATE) rk
FROM TKSTATUS where TICKETID= '12345' order by CHANGEDATE

得到了这个结果集： enter image description here

在我数1后......得到4。

我期待这个结果但是找不到我怎么做：

，结果为6.

我知道不是这样做的，因为它会在排名前将TICKETID和OWNERGROUP分组。

我会继续找到一种方法来做到这一点，但我想看看是否有人有想法。

Answer 1

在SQL Server 2012中，您可以使用lag()通过将当前行值与前一行值OwnerGroup进行比较来查看OwnerGroup更改的数量。

select 
    TicketId
  , ChangeDate
  , OwnerGroup
  , OwnerGroupChange = case 
      when coalesce(OwnerGroup,'') 
          = lag(coalesce(OwnerGroup,'')) over (partition by TicketId order by ChangeDate)
        then 0 
    else 1 
    end
from TkStatus
where TicketId = '12345'
order by ChangeDate

要获取更改数量，您可以将上述内容用作子查询或公用表表达式：

select 
    TicketId
  , OwnerGroupChange = sum(OwnerGroupChange) 
from (
  select 
      TicketId
    , ChangeDate
    , OwnerGroup
    , OwnerGroupChange = case 
        when coalesce(OwnerGroup,'') 
            = lag(coalesce(OwnerGroup,'')) over (partition by TicketId order by ChangeDate)
          then 0 
      else 1 
      end
  from TkStatus
  where TicketId = '12345'
  ) s

在SQL Server 2012之前，您可以使用outer apply()来获取之前的OwnerGroup，如下所示：

select 
    t.TicketId
  , t.ChangeDate
  , t.OwnerGroup
  , OwnerGroupChange = case 
      when coalesce(t.OwnerGroup,'') = coalesce(x.OwnerGroup,'')
        then 0 
    else 1 
    end
from TkStatus t
  outer apply (
    select top 1
      i.OwnerGroup
    from TkStatus i
    where i.TicketId = t.TicketId
      and i.ChangeDate < t.ChangeDate
    order by i.ChangeDate desc
    ) x
where t.TicketId = '12345'
order by t.ChangeDate

Answer 2

    SELECT        
    TICKETID, CHANGEDATE, OWNERGROUP, 
    DENSE_RANK() OVER (Partition by TICKETID ORDER BY CHANGEDATE) as RK
    FROM TKSTATUS where TICKETID= '12345' order by CHANGEDATE

Answer 3

你可以像这样使用CTE和LAG函数：

WITH CTE_Tickets as 
(  SELECT        
        TICKETID, CHANGEDATE, OWNERGROUP, 
        LAG(OWNERGROUP, 1) OVER (Partition by OWNERGROUP ORDER BY CHANGEDATE, OWNERGROUP ) as Prev
        FROM TKSTATUS where TICKETID= '12345')


    SELECT        
       TICKETID, CHANGEDATE, OWNERGROUP, Prev ,
       IIF(OWNERGROUP=Prev, 0, 1)  as changestatus
       FROM CTE_Tickets
       ORDER BY CHANGEDATE  , OWNERGROUP

Rank（）结束多个分区

3 个答案: