Calendars, Schedules, Tasks, and Triggers › Calendars › The Advanced Calendar Designer

The Advanced Calendar Designer

Advanced calendar rules are hierarchical tree structures. The Advanced tab for a Calendar object always shows three sets of calendar rules:

• Manually Included Dates
• Manually Excluded Dates
• Calendar Rule

These three root elements for a calendar rule are fixed. These three sets cannot be deleted. Define rules by building date conditions in the root elements. A calendar rule combines date operators (such as day of the month, month of the year, or week of the year) with logical operators (Intersection, Union, Exclusion, and Like). The Calendar Rule is actually the root Union operator for all Calendar rules.

Start building a calendar rule by dragging a rule arranged by icon under All Rules to the Calendar Rule set. You can also manually include or exclude dates.

After you place a rule under Calendar Rules, you configure its properties.

Properties for a date condition object in a calendar rule also have properties that you can expand to configure the date condition, such as the Month Interval properties.

For example, if the Month Interval properties sets Step to “3”, it specifies that every third month in a year is valid. Because the interval starts in January and ends in December, this three-month interval repeats throughout the year. This rule defines a condition for performing tasks each trimester.

The following task example shows this condition in a rule and adds a condition that specifies the fifth day of every month. The Intersection operator behaves as a logical And to combine these two conditions in a single rule that specifies the fifth day of every trimester.

Example: Create a rule specifying the fifth day of every trimester

1. Drag Intersection operator to Calendar Rule.
2. Drag Month Interval under Intersection.
3. Click the Month Interval operator. Define a Month Interval from January to December with the Step set to 3.
4. Drag a Day Interval operator under Intersection and specify an interval from 5 to 5 with the Step set to 1.
5. To save your changes to the working version of the Calendar object, click Save and Close.
6. To test the Calendar click the Preview tab.

You can continue to add additional operators and conditions to define a rule further. The logical hierarchy defines the order in which conditions are applied.

In terms of a Boolean equation, you can picture a Calendar object as enclosing parentheses around and applying Boolean constraints to subordinate operators and conditions.

• The Union operator applies a Boolean OR to subordinate operators and conditions.
• The Intersection operator applies a Boolean AND to subordinate operators and conditions.
• The Exclusion operator applies a Boolean NOT to an excluded condition.
• The Like operator inserts another calendar rule into an equation, so you can think of it as inserting a user-created Boolean function. A Calendar rule or combination of Calendar rules can handle virtually any scheduling problem.

Note that depending on the needs of a particular scheduling problem, there are multiple ways to build calendar rules. You can also define a set of dates in a separate calendar. You can use a Like operator to specify the calendar object, and add it directly under the Calendar Rule. You can also use a Union, Intersection, or Exclusion operator to include a Like operator in a calendar rule.