How to add a Query Drop Down (Single Select) field to the form validation work flow?

I have a Query Drop Down (Single Select) field that picks up some values from the db. How do I add validation to that field on registration and edit?

There's nothing to validate. The values are not user input and are coming from a query that you've constructed. So it's not possible or necessary to add validation. If you want them to be uniquely selected you can adjust the database query to JOIN _comprofiler and make sure a value hasn't been selected.

"it's not possible"
... ok, when will it be?

" or necessary to add validation"
... it is necessary : when the field is requiered and the user did not choose an option, so I need validation to validate the current option is not "-"

... ok, when will it be?

Never, there is nothing to validate.

... it is necessary : when the field is requiered and the user did not choose an option, so I need validation to validate the current option is not "-"

Set the field as required. It handles required same as any other field. The value "-" is valid, it needs to be an empty string. It uses the same API as a normal select field except it passes the options array from the result of your query instead of from the field values database table. CB automatically adds the blank value to a select field so you shouldn't need to add one.

CB automatically adds the blank value

... not in my CB, first option is a value from the db, not a blank. What could be missing here?

... not in my CB, first option is a value from the db, not a blank. What could be missing here?

Please see the below of it working fine. If it's non-required there will always be a blank. If it's required and there isn't a value (e.g. registration) then there will be a blank. If it's required and there is a value (e.g. profile edit) then there will not be a blank.

Non-Required:



Required: