SELECT DISTINCT A.EMPLOYEENAME
FROM Attendance AS A
JOIN Attendance AS B ON B.LEAVE_DATE = A.LEAVE_DATE + 1 AND B.EMPLOYEENAME = A.EMPLOYEENAME
JOIN Attendance AS C ON C.LEAVE_DATE = B.LEAVE_DATE + 1 AND C.EMPLOYEENAME = B.EMPLOYEENAME
Die inneren Verknüpfungen entfernen alle Mitarbeiter, die nicht an drei aufeinanderfolgenden Tagen abwesend waren.
