The sequential process pattern is the simplest fundamental process pattern there is and a great place to start.
The process pattern starts and ends the same way for all patterns:
- Start shape - provides a clear and necessary way to indicate where the process starts, leading to the first activity.
- End shape - determines the endpoint of the process, directed to this by the last activity
Note: It possible to define multiple starts and stop points but in the interest of clarity, well assume here the simplest and most common usage.
If a start and stop are not used, validation errors will pick this up, and the workflow process won't be deployable.
In between the start and the stop shapes, any number of Activities can be placed.
In this simple sequence, the Start will transition to A, then from A-to-B, followed by B-to-C, then to Stop. These activities all happen within the context of one ticket, and that ticket can only be A, B, or C at any one time.
This sequence pattern represents chooses. From A you can transition to B or C, as represented by the two transition links from A. The transitions from B-to-D, and C-to-D, shows how more than one transition link can be made into an activity. As such, there are two paths that can be taken through this process model:
If Path 1. is taken, then C will not be used, if Path 2. is taken, then B will not be used.
This last sequence type involves a loopback choice. C can either progress to D or loopback around to B.
All examples are all sequence, the more transitions choices and activities, the greater number of possible paths