Bereken werktijd uit ploegen- en pauzetabel

Zoals anderen al hebben gezegd, is dit een beetje vaag zonder een paar dingen aan te nemen. Er zijn snellere, minder gecompliceerde manieren om dit probleem op te lossen, maar ik heb geprobeerd mijn oplossing zo dynamisch mogelijk te maken om aan de vage definitie te voldoen. Dit zijn mijn aannames:

Hier is de SQL Fiddle:SQL Fiddle-demo

Aannames

• Ervan uitgaande dat SQL Server 2005+
• Ervan uitgaande dat het datumgedeelte van de ploegentabellen 1900-01-01 is
• Er wordt aangenomen dat de Break-tabel de juiste datum heeft voor StartTime / EndTime
• Er wordt aangenomen dat slechts 1 persoon in de database in- en uitklokt (NoEmployeeID opgenomen in @BREAK-tabel)
• Veronderstelt het werk dat ze in hun geheel verschuiven. Precies inklokken aan het begin van de dienst en uitklokken aan het einde van de dienst.

Tafels

DECLARE @SHIFT Table (ID INT IDENTITY(1,1) PRIMARY KEY, StartTime DATETIME, EndTime DATETIME)
INSERT INTO @SHIFT (StartTime, EndTime) VALUES 
('07:20:00','15:20:00'),
('15:20:00','23:20:00'),
('23:20:00','07:20:00')

DECLARE @BREAK Table (ID INT IDENTITY(1,1) PRIMARY KEY, StartTime DATETIME, EndTime DATETIME)
INSERT INTO @BREAK (StartTime, EndTime) VALUES
('1/1/2013 09:10:00','1/1/2013 09:25:00'),
('1/1/2013 11:30:00','1/1/2013 12:05:00'),
('1/1/2013 13:30:00','1/1/2013 13:45:00'),
('1/1/2013 17:10:00','1/1/2013 17:25:00'),
('1/1/2013 19:30:00','1/1/2013 20:05:00'),
('1/1/2013 21:30:00','1/1/2013 21:45:00'),
('1/2/2013 01:10:00','1/2/2013 01:25:00'),
('1/2/2013 03:30:00','1/2/2013 04:05:00'),
('1/2/2013 05:30:00','1/2/2013 05:45:00'),

('1/2/2013 09:10:00','1/2/2013 09:25:00'),
('1/2/2013 11:30:00','1/2/2013 12:05:00'),
('1/2/2013 13:30:00','1/2/2013 13:45:00'),
('1/2/2013 17:10:00','1/2/2013 17:25:00'),
('1/2/2013 19:30:00','1/2/2013 20:05:00'),
('1/2/2013 21:30:00','1/2/2013 21:45:00'),
('1/2/2013 01:10:00','1/2/2013 01:25:00'),
('1/2/2013 03:30:00','1/2/2013 04:05:00'),
('1/2/2013 05:30:00','1/2/2013 05:45:00')

Oplossing

;WITH
MinMaxDates AS --FINDS THE MINIMUM AND MAXIMUM DATE RANGES NEEDING SHIFTS ASSOCIATED.
(
    SELECT 
        CAST(MIN(B.StartTime) AS DATE) AS MinDate, 
        CAST(MAX(B.EndTime) AS DATE) AS MaxDate 
    FROM @BREAK AS B
),
RecursiveDateBuilder AS --RECURSIVELY BUILDS A LIST OF DATES BETWEEN THE MINIMUM AND MAXIMUM RANGES IN BREAKS
(
    SELECT MinDate AS ShiftStartDate FROM MinMaxDates
    UNION ALL
    SELECT DATEADD(dd,1,ShiftStartDate) FROM RecursiveDateBuilder WHERE DATEADD(dd,1,ShiftStartDate) <= (SELECT MaxDate FROM MinMaxDates)
),
ShiftSets AS --CREATE A SHIFT SET FOR EVERY DATE
(
    SELECT 
        ROW_NUMBER() OVER (ORDER BY R.ShiftStartDate ASC, S.ID ASC) AS NewShiftID,
        S.ID AS OldShiftID, 
        DATEADD(dd,DATEDIFF(dd,S.StartTime, R.ShiftStartDate),S.StartTime) AS StartDate,
        DATEADD(dd,DATEDIFF(dd,S.EndTime, R.ShiftStartDate),S.EndTime) AS EndDate,
        R.ShiftStartDate AS ShiftGroup
    FROM
        @SHIFT AS S
        CROSS JOIN RecursiveDateBuilder AS R
),
Shifts AS  --FIXES ANY SHIFTS THAT CROSS MIDNIGHT SETTING THEM TO THE NEXT DAY
(
SELECT
    S.NewShiftID AS ShiftID,
    S.StartDate,
    CASE 
        WHEN S.EndDate <= Min2.MinStartDate THEN DATEADD(DAY,1,S.EndDate) 
        ELSE S.EndDate 
    END AS EndDate
FROM
    ShiftSets AS S
    CROSS APPLY (SELECT MIN(Mins.StartDate) AS MinStartDate FROM ShiftSets AS Mins WHERE Mins.ShiftGroup = S.ShiftGroup) AS Min2 
),
BreaksToShifts AS  --ASSOCIATES THE PUNCHES TO THE SHIFTS
(
    SELECT
        B.StartTime AS ClockIn,
        B.EndTime AS ClockOut,
        S.ShiftID,
        S.StartDate,
        S.EndDate
    FROM
        @BREAK AS B
        INNER JOIN Shifts AS S ON (B.StartTime BETWEEN S.StartDate AND S.EndDate AND B.EndTime BETWEEN S.StartDate AND S.EndDate)
),
Punches AS
(
    SELECT ROW_NUMBER() OVER (ORDER BY S.TheTime ASC) AS ID, S.TheTime FROM 
    (
        SELECT BS.ShiftID, BS.ClockIn AS TheTime FROM BreaksToShifts AS BS
        UNION ALL
        SELECT BS.ShiftID, MIN(BS.StartDate) AS TheTime FROM BreaksToShifts AS BS GROUP BY BS.ShiftID
        UNION ALL
        SELECT BS.ShiftID, BS.ClockOut AS TheTime FROM BreaksToShifts AS BS
        UNION ALL
        SELECT BS.ShiftID, MAX(BS.EndDate) AS TheTime FROM BreaksToShifts AS BS GROUP BY BS.ShiftID
    ) AS S
)
SELECT
    *
FROM
    Punches AS P1
    INNER JOIN Punches AS P2 ON (P2.ID = P1.ID + 1)
WHERE
    P1.ID % 2 > 0