A workflow with parallel steps consists of multiple independent parallel streams, each comprising a series of concurrent steps. These streams operate autonomously and progress independently, with no interdependency across different streams. Although the sequence of execution within a single stream is flexible, all tasks must be completed before advancing to the final Exit activity.
To initiate parallel execution, use the Split activity to divide a task into multiple parallel subtasks. The Merge activity is used to consolidate these paths into a single flow, signifying the end of the parallel execution. For more information, see Overview of Workflow Designer.
When parallel activities are created simultaneously, the application automatically groups them into a single unit. However, it is essential to manually configure the sequence of Split, Merge, and other parallel activities in the Properties panel. For workflows with multiple parallel groups, ensure that the order of their execution corresponds to the order in which the Split activities are defined.
Guidelines for Sequencing Parallel Workflow Steps:
Following are the guidelines for sequencing parallel workflow steps:
- Split nodes and Merge nodes shall follow the same sequential numbering convention as other workflow steps.
- Each parallel stream must be named using the Split node number followed by a letter (For example, 2a, 2b, 2c, and so on). Steps within a stream must be numbered accordingly, for example 2a.1, 2a.2 for stream 2a, and 2b.1, 2b.2 for stream 2b, and so on.
- Each sequence must be a unique user defined sequence ID to avoid any potential issues.
A sample workflow demonstrating this structure is displayed.
Create a new workflow with parallel steps
Following are the steps to create a workflow which includes parallel steps:
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On the navigation menu, click Configurations > Workflow Designer app.
Result: The Workflow Designer page is displayed. -
Select Create New Workflow from the Select Workflow drop-down.
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Drag and drop the Split activity from the Activities panel into the Activity Builder and link it to Start activity using appropriate arrows.
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Click the Split activity from the Activity Builder panel.
Result: The Properties panel is displayed. -
Enter the sequence number for the Split in the Sequence field as displayed.
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Drag and drop an activity from the Activities panel to the Activity Builder and link the activities using appropriate arrows.
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Select the Human Work activity from Activity Builder panel and fill the details in the relevant fields of the Properties panel. Input the sequence as 1a.1, as it is a first step under the first group. For more information on Properties panel, see Overview of Workflow Designer.
A sample screenshot of the Properties panel for the activity is displayed.
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Add more parallel steps as needed, providing the relevant details for each in the Properties panel. Additional steps within the same group will be named 1a.2, 1a.3, and so on. Each parallel step will be grouped separately and outlined in a yellow box as displayed in the image.
A sample screenshot is displayed.
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Click on the arrow to provide suitable action names in the Properties panel.
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Add more steps as necessary, input the relevant details, and sequence them in the Properties panel. New parallel steps will be named 1b.1, 1c.1, 1d.1, and so on.
A sample screenshot is displayed.
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Repeat steps 8 and 9 to continue adding activities and actions to design the workflow.
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Drag and drop the Merge activity from the Activities panel into the Activity Builder to combine all the parallel workflow steps into a single point.
A sample screenshot is displayed.
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Select the Merge activity in the Activity Builder panel and enter appropriate sequence in the Sequence field. In this example, merge can be provided a sequence of 2.0.
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Drag and drop any activity from the Activity Builder panel and link the Merge activity to this using arrows.
A Merge cannot be directly linked to the End activity. It must first be connected to another activity before ending the workflow.
A sample screenshot is displayed.
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Drag and drop the End activity and link the previous activity to it using arrows.
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Click Save to publish the newly created workflow.
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Enter the Workflow Name, Workflow Long Name, and Workflow Version and click Save.
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Click the Refresh icon to view the newly created workflow in the Selected Workflow drop-down.
- There is no limit to the number of parallel steps you can include within a single parallel stream.
- Only grouped activities (those within a parallel group) can be linked to a Merge activity. Individual, ungrouped activities cannot be connected directly to a Merge.
- A workflow cannot begin with a Merge as the initial step.
- Activities within a parallel stream cannot be connected to activities outside of that stream.
- A grouped activity cannot be directly connected to a Split.
- A group can contain only one Split.
- A grouped activity cannot be linked from any other activity; it can only be connected to a non-group activity.
- For a Split activity, following are the key points:
- A Split must lead to at least two parallel steps.
- A Split can originate multiple parallel streams.
- A Split cannot directly follow another Split.
- Each Split must be paired with a single corresponding Merge activity.
- You can place a Split immediately after a Merge without any intermediate activity.
- For a Merge activity, following are the key points:
- A Merge can have only one incoming connection from each parallel stream.
- A Merge cannot directly follow another Merge.
- A Merge cannot be directly connected to a Start or End event.
Limitations
Following are the limitations:
- Transitions between steps are only permitted within the same parallel group. Transition to a step outside the parallel group is allowed only after the Merge activity.
- Nested branching is not supported, which means a group cannot have a split within it.
Import Parallel workflow steps using Workflow App model
You can import a workflow with parallel steps via Workflow App data model. However, it is important to select the Merge and Split activities from the Activity Type drop-down wherever it is required. To support parallel workflow steps, a new column Split Group ID is introduced in the Workflow Activity Definition sheet, where you can enter the sequence of each parent group of a parallel workflow step. For more information, see Populate Workflow Activity Definition.
A screenshot of Workflow Activity Definition sheet for a workflow with parallel steps is displayed.
Once a workflow is modelled using Workflow Designer or imported through App Model, you can manage and track it on the UI and complete your assigned tasks step by step. For more information, see Manage Parallel Workflow Steps.
Keywords to support Parallel Workflow Steps
The following keywords are enhanced to support additional activities that entity participates, when an entity is part of parallel workflow steps.
Walkthrough
Here is a quick walkthrough on how to create a workflow with parallel steps using Workflow Designer.