按日期選擇相同組的列到不同的列

Question

我登錄的表看起來像這樣：

Created    | Action 
20/01/2016 08:00:00 AM login 
20/01/2016 10:05:10 AM logout 
20/01/2016 12:00:00 PM login 
20/01/2016 04:12:22 PM logout 
21/01/2016 08:00:50 AM login 
21/01/2016 09:44:42 AM login 
21/01/2016 10:44:42 AM login 
21/01/2016 04:00:42 PM logout 

我需要選擇一個結果集，看起來像這樣：

Created  | Login | Logout   
20/01/2016  08:00:00 AM 04:12:22 PM 
21/01/2016  08:00:50 PM 04:00:42 PM 

這裏是我曾嘗試過的：

SELECT 
    CONVERT(VARCHAR(10),li.Created,10) [Date], 
    CONVERT(VARCHAR(8),MAX(li.Created),8) [Login], 
    CONVERT(VARCHAR(8),MAX(lo.Created),8) [Logout] 
FROM Logins li 
LEFT JOIN Logins lo ON lo.[Action] = 'logout' 
GROUP BY li.Created 

但是結果沒有按日期分組。

什麼是正確的方法？

Answer 1

與Rahul的回答類似，但您可以自行加入以獲取第一次登錄/最後一次登出，並按日期分組以獲得您要求的結果;

SELECT CONVERT(DATE,  li.created) [Date], 
     CONVERT(TIME, MIN(li.created)) [Login], 
     CONVERT(TIME, MAX(lo.created)) [Logout] 
FROM Logins li 
JOIN Logins lo 
    ON CONVERT(DATE, li.created) = CONVERT(DATE, lo.created) 
AND li.action = 'login' 
AND lo.action = 'logout' 
GROUP BY CONVERT(DATE, li.created) 

An SQLfiddle to test with。

編輯：未經測試的SQL Server 2005，您可能需要設置varchars的長度;

SELECT CONVERT(VARCHAR, li.created, 110) [Date], 
     CONVERT(VARCHAR, MAX(li.created), 8) [Login], 
     CONVERT(VARCHAR, MAX(lo.created), 8) [Logout] 
FROM Logins li 
JOIN Logins lo 
    ON CONVERT(VARCHAR, li.created, 110) = CONVERT(VARCHAR, lo.created, 110) 
AND li.action = 'login' 
AND lo.action = 'logout' 
GROUP BY CONVERT(VARCHAR, li.created, 110) 

Another SQLfiddle。

Answer 2

你可以嘗試這樣的：

SELECT 
CONVERT(VARCHAR(10),li.Created,10) [Date], 
CONVERT(VARCHAR(8),MAX(li.Created),8) [Login], 
CONVERT(VARCHAR(8),MAX(lo.Created),8) [Logout] 
From Logins li 
Left Join Logins lo on lo.[Action] = 'logout' 
GROUP BY CAST(li.Created AS DATE) 

即，你需要按您的記錄上的日期，而不是按日期和時間兩者。

Answer 3

我打算假設您的結果20日上午4點註銷是一個疏忽，否則我們需要知道確定它應該被視爲當天註銷時間的邏輯。

一個問題是，您試圖僅顯示日期作爲您的組，但您按照日期和時間進行分組。

試試這個：

SELECT 
    CAST(LI.created AS DATE) AS created, 
    MIN(CAST(LI.created AS TIME)) AS login, 
    MAX(CAST(LO.created AS TIME)) AS logout 
FROM 
    dbo.My_Table LI 
LEFT OUTER JOIN dbo.My_Table LO ON 
    LO.action = 'logout' AND 
    CAST(LO.created AS DATE) = CAST(LI.created AS DATE) 
WHERE 
    LI.action = 'login' 
GROUP BY 
    CAST(LI.created AS DATE) 

另一個要考慮的是，是否登錄時間可以跨越的日期範圍。如果這是科技行業的話，登錄1/20晚上10點和登出1/21凌晨2點並不奇怪。 ;）