postgresql create trigger update timestamp

CREATE OR REPLACE FUNCTION public.set_current_timestamp_updated_at()
 RETURNS trigger
 LANGUAGE plpgsql
AS $function$
DECLARE
  _new record;
BEGIN
  _new := NEW;
  _new."updated_at" = NOW();
  RETURN _new;
END;
$function$


CREATE TRIGGER set_updated_at
BEFORE UPDATE ON your_table
FOR EACH ROW
EXECUTE FUNCTION set_current_timestamp_updated_at();