DELETE r1 FROM pp_redirects r1
INNER JOIN pp_redirects r2
  ON r1.`from` = r2.`from`
 AND (r1.lang_id <=> r2.lang_id)
 AND (
      IFNULL(r1.date_add, '1000-01-01 00:00:00') < IFNULL(r2.date_add, '1000-01-01 00:00:00')
      OR (
        IFNULL(r1.date_add, '1000-01-01 00:00:00') = IFNULL(r2.date_add, '1000-01-01 00:00:00')
        AND r1.id < r2.id
      )
    );
