The calendar database records represent the scheduling time periods. Each time period has a name and a start date. The difference between the start date for one period and the start date for the following period, defines the length of that time period. Consequently, you must always create one more time period than you need to be able to define the length of all required time periods.

The time periods that are used for scheduling are the lowest level records across the calendar structure. As with any XPAC database, it is in these lowest level records that the data is stored. Upper level records are simply an accumulation of lower level record data.

In the example below, you can see the lowest level records (i.e. the scheduling time periods) shaded in blue.