Question

我不确定我是否过于复杂这么小的任务，但是如果有人能帮助我一点正确的方向，那么我将不胜感激。

我有两个具有相同字段的表，我创建了一个包含这两个值的视图。

正如我所说的那样：

    SELECT TOP 1000 [Name]
      ,[WorkOrder]
      ,[OnSiteStarted]
      ,[OnSiteSubmitted]

  FROM [DBName].[dbo].[sw_onsite_offsite]
  ORDER BY WorkOrder

结果集显示为（片段）：

Name       WorkOrder      OnSiteStarted          OnSiteSubmitted
On-Site     23022017    2017-02-23 20:31:49.000  2017-02-23 20:33:47.000
Off-Site      35        2017-02-15 18:32:26.000  2017-02-15 21:11:04.000
On-Site     64169086    2017-02-22 11:42:40.000  2017-02-22 15:10:17.000
Off-Site    91487689    2017-02-11 13:48:11.000  2017-02-11 14:32:37.000
On-Site     91494707    2017-02-13 14:39:42.000  2017-02-13 14:49:03.000
Off-Site    92810031    2017-02-17 09:30:59.000  2017-02-17 09:58:19.000
On-Site     92810031    2017-02-17 09:00:12.000  2017-02-17 09:30:48.000
Off-Site    92810034    2017-02-17 10:01:27.000  2017-02-17 10:24:45.000
On-Site     92810039    2017-03-03 12:33:41.000  2017-03-03 12:52:37.000
Off-Site    92810039    2017-03-03 12:44:52.000  2017-03-03 13:41:35.000

我所追求的最终结果是：当场外和现场表格具有相同的WorkOrder编号时，这将仅显示它们与DATEDIFF（MINUTES，[onsitesubmitted]，[offsitesubmitted]字段。

CASE声明会以某种方式适用于此，还是其他的？

Answer 1

我想你想要一个自我加入：

select t1.WorkOrder,
    DATEDIFF(MINUTES, t1.onsitesubmitted, t2.OnSiteSubmitted) diff
from [DBName].[dbo].[sw_onsite_offsite] t1
join [DBName].[dbo].[sw_onsite_offsite] t2 on t1.WorkOrder = t2.WorkOrder
where t1.name = 'On-Site'
    and t2.name = 'Off-Site'

这只返回那些异地和现场都有相同WorkOrder的行。如果您希望它在不匹配的情况下产生结果，则可以使用适当的外连接。

Answer 2

.catch((response: Response) => {
                return Observable.of(response);
            });

Answer 3

如果您的数据库支持它，您可以使用inspect.signature或lead()窗口函数（您没有标记数据库，但它看起来像sql-server）

lag()

sql server中的rextester演示：http://rextester.com/OTNS68646

返回：

select 
    Name
  , WorkOrder
  , OnSiteStarted
  , OnSiteSubmitted
  , datediff(minute
      , lead([onsitesubmitted]) over (
          partition by WorkOrder 
          order by Name 
        )
      , [onsitesubmitted]
     ) as Duration
from [dbo].[sw_onsite_offsite]
order by WorkOrder, OnSiteSubmitted

SQL CASE IF [VALUE]当[Value]和[VALUE]那么

3 个答案: