Sometimes it is preferrable to output full name as a single field/column like
<last_name>, <title> <first_name>
where title and first name are both optional (as occurs in the real world). Because of the different combinations where title and/or first name are null there should be some conditional logic with concatenation. But you can do correct concatenation in a single expression using the fact that coalesce(right(title,0),', ') will return empty string when title is not null and separator', ' otherwise:
select
trim(
upper(family_name) || coalesce(', ' || title || ' ', '') || coalesce(coalesce(right(title,0),', ') || given_names, '')
) as person_name
from person
