Question

我在sql中有2个表

1. SELECT TOP 1000 [UserId]
      ,[UserName]
      ,[Password]
      ,[FirstName]
      ,[LastName]
      ,[Password_Expiry]
      ,[Modified]
      ,[ModifiedBy]
      ,[CreatedBy]
      ,[Type]
      ,[Privileges]
  FROM [Paramount].[dbo].[UserProfile]



2. SELECT TOP 1000 [Id]
      ,[UserId]
      ,[ClockInClockOutTypeId]
      ,[CreatedDate]
  FROM [Paramount].[dbo].[ClockInClockOut]

我需要从两个表中检索数据，如 -

[UserName]| Date [CreatedDate]|[CreatedDate](just time in) as TimeIn | [CreatedDate](just Time Out) as time out 
Mr.abc xyz| 4/12/13           | 1:30 Pm                              | 3:30Pm

我试过这个但没有得到所需的结果： -

SELECT u.[username], 
       c.[clockinclockouttypeid], 
       c.[createddate] 
FROM   [Paramount].[dbo].[clockinclockout] AS c 
       JOIN [Paramount].[dbo].[userprofile] AS u 
         ON c.userid = u.[userid] 
WHERE  c.[clockinclockouttypeid] = 1 

SELECT u.[username], 
       c.[clockinclockouttypeid], 
       c.[createddate] 
FROM   [Paramount].[dbo].[clockinclockout] AS c 
       JOIN [Paramount].[dbo].[userprofile] AS u 
         ON c.userid = u.[userid] 
WHERE  c.[clockinclockouttypeid] = 2 rProfile] as u on c.UserId = u.[UserId] where c.[ClockInClockOutTypeId]=2

任何帮助将不胜感激，提前感谢！

Answer 1

尝试这样的UNION

select [UserName], MAX([Date]) as [Date], MAX(InTime) as InTime, MAX(OutTime) as OutTime
FROM (
    select u.[UserName],
           CONVERT(VARCHAR(20), c.[CreatedDate], 101) as [Date],
           CONVERT(VARCHAR(20), c.[CreatedDate], 108) as InTime,
           null as OutTime
    from [ClockInClockOut] as c 
    inner join [UserProfile] as u on c.UserId = u.[UserId] 
    where c.[ClockInClockOutTypeId]=1 

    UNION 
    select u.[UserName],
           CONVERT(VARCHAR(20), c.[CreatedDate], 101)  as [Date],
           null as InTime,
           CONVERT(VARCHAR(20), c.[CreatedDate], 108)as OutTime
    from [ClockInClockOut] as c 
    inner join [UserProfile] as u on c.UserId = u.[UserId] 
    where c.[ClockInClockOutTypeId]=2
) tt
GROUP BY [UserName]

<强> SQL Demo 1

更新：

您也可以使用以下情况：

select [UserName], MAX([Date]) as [Date], MAX(InTime) as InTime, MAX(OutTime) as OutTime
FROM
(
   select u.[UserName],
          CONVERT(VARCHAR(20), c.[CreatedDate], 101) as [Date],
          CASE WHEN c.[ClockInClockOutTypeId]=1 THEN CONVERT(VARCHAR(20), c.[CreatedDate], 108) ELSE null END as InTime,
          CASE WHEN c.[ClockInClockOutTypeId]=2 THEN CONVERT(VARCHAR(20), c.[CreatedDate], 108) ELSE null END as OutTime
   from [ClockInClockOut] as c 
   inner join [UserProfile] as u on c.UserId = u.[UserId] 
) tt
GROUP BY [UserName]

<强> SQL Demo 2

Answer 2

SQL连接子句（对应于关系代数中的联接操作）将来自关系数据库中一个或多个表的列组合在一起。我们知道SQL中的内部联接，左联接，自然联接等。但是大多数人不知道什么是自我加入以及它如何运作？现在我们将要了解什么是自我联接及其作用方式。当表本身引用数据时，我们可以使用自连接。为了清楚地了解，请参见下表。

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如何在sql中使用self join？

2 个答案: