create or replace function find_citizen_by_id(in id uuid, out resource json) language plpgsql as $$ declare _id alias for id; begin select to_json(t) into resource from ( select z.*, find_user_by_id(z.user_id) from citizen as z where z.id = _id ) as t; end; $$; -- drop function if exists find_citizen_by_id(uuid, inout json);