I try to stay away from single table schemas for any solution. However, if I understand your question, I would simply have a table containing columns that could contain all the possible relevant information. In addition I would have a column for begin and another column for the end date. If you want to use julian dates in these columns that is ok, just relate this table with a time table. You would then have just one entry for each sick leave or holiday vacation instead of one entry per day or per hour etc. . . Your stored procedure could figure out how much time the actual sick leave took where it might cover weekends and holidays based on the relationship to your timetable.