The DEAT Business Rule Pattern Language

Russell R. Hurlbut, Ph.D.

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Rule Pattern 22: Scheduled Execution

Problem Describing Actions that must occur at a Specific or Relative Point in Time

Maintaining schedules of required actions is a common business problem. Actions may be performed at a specific point in time, but often that point in time is influenced by the day of week or intervening holidays. Alternatively, the timing of performing an action may be relative to some event.


Scheduled execution of activities may be accomplished through definition of calendar types and duration subtypes. The calendar provides for absolute points in time. Scheduled execution of an action may then be determined from the base point in time and the extent, or duration. This concept of date-time manipulation was previously introduced in the Attribute Interval pattern.

Example Case Resolution

A customer service department policy stipulates that any case that remains open for more than 14 days must be escalated in its priority status. In this example a standard 365 day calendar is used. This implies that no allowances are made for weekends or holidays. The policy may be restated as ten days with use of the corporate work calendar.
Case Resolution Parameters
Schedule Type Relative
Recurrence <No>
Start Event Case Opened
Duration 14 days
Calendar Basis 365 Day

Example Course Calendar

The training schedule for a calendar year must be prepared and distributed by the second Monday in November of each year. The use of dates established relative to a calendar is a common situation that relies on collaboration with the Ordering pattern business rule pattern. In contrast to previous examples, the parameters for both are presented in order to illustrate the specialized application of the functional restriction parameter of the Ordering pattern. Essentially, the application of the functional restriction in the more generalized parameters can be translated as follows: Give me the member date in the month of November dates collection that is ordered by date and has exactly one member element preceding it for which the day of week is Monday. The shorthand parameters consolidate the condition of the member element with the preceding elements and set a more intuitive order parameter rather than preceding count parameter. This one parameter replaces five from the more general case.
Course Calendar Parameters
Schedule Type Calendar
Recurrence Annual
Start Event Nov 1
Order 2
Condition dayOfWeek = Monday
Scope ALL
Direction preceding
Count 1
Comparative =
Condition dayOfWeek = Monday


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