In Orbeon Forms 2018.2.2 PE, we introduced the ability for you, as a form author, to mark form fields as encrypted at rest, by simply checking a checkbox in Form Builder. When doing so, with no additional effort, the values of those fields will, at all times, be encrypted in your database.
Checkbox to mark field for encryption
You might want to encrypt the values of fields you deem sensitive, for instance to prevent access to those values even to a person who has access to your database, such as a database administrator, or a hacker in case your database server has been compromised. This feature can help you comply with data protection and privacy regulations, such as GDPR.
For more detailed information about this feature, see the page Field-level encryption in the Orbeon Forms documentation.