Calculate time difference for attendance

Question

I have a table with the below sample output.

UserID  Checktime              CheckStatus
3175    2013-12-22 07:02:10.000     I
3175    2013-12-22 13:01:01.000         


        

Answer 1

I took Devart's code and improved it. What I do is I use OUTER APPLY to grab the next row for each "IN" status. I then sort out the bad rows in the where clause. If there are two "IN" in a row, then it grabs the later one.

DECLARE @temp TABLE
(
    UserID INT,
    Checktime DATETIME,
    CheckStatus CHAR(1)
)

INSERT INTO @temp (UserID, Checktime, CheckStatus)
VALUES 
    (3175, '20131222 07:02:10.000', 'I'),
    (3175, '20131222 13:01:01.000', 'O'),
    (3175, '20131222 13:49:54.000', 'I'),
    (3175, '20131222 13:49:55.000', 'I'),
    (3175, '20131222 15:58:42.000', 'O'),
    (3175, '20131223 06:02:58.000', 'I'),
    (3175, '20131223 14:00:29.000', 'O'),
    (3175, '20131224 05:17:09.000', 'I'),
    (3175, '20131224 12:34:25.000', 'O'),
    (3175, '20131224 12:34:26.000', 'O')

SELECT  UserID,
        CAST(I.CheckTime AS DATE) AS [Date],
        CONVERT(VARCHAR(10), I.CheckTime, 108) AS CheckIn,
        CONVERT(VARCHAR(10), O.CheckTime, 108) AS CheckOut,
        CAST(DATEDIFF(MINUTE,I.checkTime,O.CheckTime)/60.0 AS DECIMAL(18,2)) [Hours]
FROM @temp I
OUTER APPLY (
                SELECT TOP 1    Checktime,
                                CheckStatus
                FROM @temp t
                WHERE       t.UserID = I.UserID
                        AND t.Checktime > I.Checktime
                ORDER BY t.Checktime
            ) O
WHERE I.CheckStatus = 'I'
AND O.CheckStatus = 'O'

Results:

UserID      Date       CheckIn    CheckOut   Hours
----------- ---------- ---------- ---------- -----
3175        2013-12-22 07:02:10   13:01:01   5.98
3175        2013-12-22 13:49:55   15:58:42   2.15
3175        2013-12-23 06:02:58   14:00:29   7.97
3175        2013-12-24 05:17:09   12:34:25   7.28