Data Driven Events

In an application or questionnaire, data driven events (DDEs) enable you to evaluate conditions within a record and take dynamic actions based on those conditions. A DDE is made up of a rule ("if X happens") and an action ("then do Y").

If you want to build an entire business process, consider advanced workflow.

DDEs are available for on-prem, hosted, and SaaS deployments.

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Rules and actions

A rule is a set of one or more data conditions or values that must be met for the rule to evaluate to true. Rules are evaluated in a specified rule order that you assign. A rule can be linked to one or more actions.

An action is a predefined operation that is executed when linked to a rule. Actions are executed only when the rule to which they are linked is evaluated as true. Actions are reusable across multiple rules, but are owned by the application or questionnaire and are not available to other applications or questionnaires. In leveled applications, rules and actions are defined in the context of a specific level and are not available to other levels.

Rules are evaluated and actions are executed in a rules session, which is a single uninterrupted pass of evaluating rules in a specified order and executing linked actions for any rules that are true. A rules session is invoked when a record is added, changed, or saved.

Action types

There are four action types:

  • Apply Conditional Layout actions allow you to change the layout of the record. For example, you can display or hide sections or change the properties of individual fields, such as privacy settings.
  • Filter Values List Items actions allow you to restrict the values available for users to select in a values list field.
  • Set Date actions allow you to set a value for a date field (which can be overridden).
  • Set Values List Selection actions allow you to set a specific value in a values list field (which can be overridden).

Considerations for using DDEs

Consider the following when defining data drive event (DDE) rules and actions:

  • A default display action to show sections is not required. By default, all layout objects are shown. The only time that you need to explicitly show a layout object is when another ACL action needs to be overridden.
  • It is not recommended to use rules with the changed operator in ACL or Filter Values List Items actions. The action is inconsistent from one save to another because the rule is true before the save and false after. For additional information on changed operators, see rules for evaluating changed operators.
  • Do not associate rules evaluating only calculated fields with the Set Date or Set Values List Selection actions. This action type is never executed because calculations are not updated until after these actions are executed. These actions require a triggering field to be included in the rule linked with the action.

When building DDEs, consider the following guidelines:

  • Required fields that are hidden from the end user in an application are still required. Users cannot save the record when this condition exists.
  • Fields that are hidden in an application and are set to be required by an Apply Conditional Layout (ACL) action are only required conditionally. When hidden fields are conditionally required by an ACL, users can save the record.
  • A rule condition that evaluates a Text field with the Display Control set to Text Area may result in inconsistencies due to rich text markup when an operator other than Contains or Does Not Contain is used.
  • Tabs can be dynamically shown or hidden based on the current state of content, including nested tabs. When a data driven event hides all sections on a tab, the tab is also hidden.
  • Actions linked to the rule targeting a private field may not execute because not all users can access the private field. Field permissions can be different for each user.
  • Date and Values List field values that are set by an action can still be edited by the end user unless the field is set to not be edited. For example, all other values in a Values List are filtered by an action.

Conflict resolution and troubleshooting DDEs

Depending on how rules are configured in an application or questionnaire, it is possible that the actions defined for those rules could conflict with each other. It is important to understand the effects and expected behaviors that can occur when an action is executed. Each action type includes rules to consider when defining actions and suggestions for conflict resolution.

The Data Driven Event feature includes the Event Analyzer utility for troubleshooting DDE rules. The Event Analyzer provides a real-time view of rule evaluations and actions that are applied as a result of user interaction with the content edit page.

Who can work with DDEs?

To create, edit, or delete both rules and actions, your user account must specify that you:

  • Are a configuration administrator
  • Have update rights on the Manage Application page.
  • Have configuration administration rights to the questionnaire (if working on a questionnaire).