Hello @jefft !
To clarify, is the goal to keep certain users from accessing specific sensitive data by using the cascading filters? If the goal is data security, I would suggest adding RLS if you haven’t already to make sure users can only access the data they have permissions to.
What you could try is when you create the parameter, is set it to have multiple values and designate those values as 1, 2 and 3. Then for the target visual or table, create an ifelse statement that similar to this one:
ifelse(
${123Param} = '1', {Target_field} = 'target row key value',
${123Param} = '2', {Target_field} = 'target row key value 2'
${123Param} = '3', {Target_field} = 'target row key value 3'
NULL)
For the custom error message, to my knowledge there are no baked in customization options in the UI, but you could try this solution from another post that have a similar result.Preformatted text