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Storage: Stored on a database table separate from the form data. These variables are stored in the "shkactivitydata" database table and are not to be tampered with for reasons mentioned below in the section Storage mechanisms for form data variables and workflow variables.
Key Concepts
Hash Variables
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Form Data Update Tool: This built-in plugin tool is used to update values directly in the database. To use this go to to Process Builder> Tools> Mapping> Select Update Form Data> Choose Form Field to Update Fields.
The changes made using this tool affect the data stored in form fields. This tool ensures that any changes or entries made to form fields are correctly reflected in the database, without needing manual input, directly within the workflow process.
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Workflow Variable Update Tool: Available at the marketplace, the Workflow Variable Update Tool updates the value of workflow variables. To use this go to Process Builder> Tools> Mapping> Select Workflow Variable Update Tool> Choose Workflow Variable to UpdateMapping.
It's used when there's a need to modify the values of variables that control or influence the workflow process.
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While workflow variables are essential for process routing, other elements like form data and hash variables can also be used for similar purposes. For example, using a form hash variable in a transition condition e.g., ((# form.Approval_Form.status # === "Approved")) is a viable alternative to check for conditions and make decisions in the process workflow.
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Figure 5: Making the same routing decision using a Form Hash Variable in Process Builder
For this example, this status field is present in a form named Approval Form. In the above figure, we are simply checking if the value in this form is "Approved" or other than approved ("Rejected"), and then we proceed to route to the correct decision.
Figure 6: Status Field options
A key feature of workflow variables is their ability to create an audit trail. As the process progresses, In the monitor section, the variable list efficiently tracks a record's progress through the workflow.
Figure 67: Viewing a Completed Activity Instance
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