SQL時間參數計算

Question

我剛剛嘗試創建活動報告的SQL新手，我在表上存儲過程和觸發器以記錄登錄和註銷日期/時間。

我如何計算時間一些建議之後，從第一個日誌先後在持續註銷每天？

任何指導將不勝感激謝謝。

Answer 1

SELECT A.*, 
     DATEDIFF(second,B.firstloginonthatday,B.lastlogoutonthatday) AS time_elapsed 
    FROM YourTable A 
INNER JOIN 
    (  SELECT Z.USERID, 
        CONVERT(DATE,Z.DATE_TIME) AS ONLYDATE, 
        MIN(Z.DATE_TIME) AS firstloginonthatday, 
        MAX(Z.DATE_TIME) AS lastlogoutonthatday 
       FROM 
       (
        SELECT *, 
          ROW_NUMBER() 
          OVER 
          (PARTITION BY USERID,CONVERT(DATE,DATE_TIME) ORDER BY CASE WHEN action = 'logout' THEN DATE_TIME 
           ELSE NULL END 
          ) AS lastlogout_rn,    
          ROW_NUMBER() 
          OVER 
          (PARTITION BY USERID,CONVERT(DATE,DATE_TIME) ORDER BY CASE WHEN action = 'login' THEN DATE_TIME 
           ELSE NULL END 
          ) AS firstlogin_rn  
         FROM Yourtable 
       ) Z 
      WHERE Z.lastlogout_rn = 1 OR Z.firstlogin_rn = 1 
      GROUP BY Z.USERID,CONVERT(DATE,Z.DATE_TIME) 
    ) B 
    ON A.USERID = B.USERID 
    AND CONVERT(DATE,A.DATE_TIME) = B.ONLYDATE;