In order for Cascading Data Sets to function in a Unity Form, the Cascading Data Set must be configured as described in the Configuration documentation and assigned to the Document Type that will be used to store the Unity Form. To configure a Cascading Data Set on a form, place the keywords which belong to the Cascading Data Set on the form. Keyword Types may be located anywhere on the form, but for any level placed on the form, all higher levels must appear as well so that cascading can occur correctly.
The parent or root Keyword Type must be placed on the form. In order to maintain a Cascading Data Set's functionality, neither the parent/root or child/secondary Keyword Type's control type should be changed.
When using Cascading Data Sets, Unity Forms specific data sets cannot be used in conjunction with Keyword Type defined data sets. Cascading Data Sets must be configured in the Configuration module at the Keyword Type level. Overriding a Keyword Type field with a Unity Forms specific data set will disable cascading data set functionality. If you override the parent/root data set, the children/secondary data sets will not populate based on the parent/root keyword value selection. Each keyword in the Cascading Data Set within the form must have the Use Keyword Data Set option selected in order to maintain the integrity of a Cascading Data Set as a whole.
When using a Cascading Data Set, in order to place a child/secondary Keyword Type on the form, it's parent/root Keyword Type must exist on the form. If a child/secondary Keyword Type is placed on the form, and its parent/root Keyword Type does not exist, you cannot publish or test drive the form.
In the Client, in order to access data set values from a child/secondary Keyword Type, the parent/root Keyword Type must be populated first on the form.