这些是 * 子查询 *，所以-只需将它们放在适当的位置（请参阅说明的注解）：

SELECT c.srgt_key_val AS customer_id,
       CAST (i.eff_ts AS DATE) AS "EFF_DT",
       i.eff_ts,
       '9999-12-31' AS end_dt,
       'N' AS del_ind,
       'I' AS customer_type,
       CASE WHEN ctr.name = 'Canada' THEN 'Y' ELSE 'N' END AS residence_flag,
       NVL (ctr.name, 'N/A') AS country,
       NVL (
          (   TRIM (title)
           || ' '
           || TRIM (first_name)
           || ' '
           || TRIM (last_name)),
          ' ') AS name,
       NVL (
          (   TRIM (city)
           || ' '
           || TRIM (post_code)
           || ' '
           || TRIM (street)
           || ' '
           || TRIM (unit_nbr)
           || ' '
           || TRIM (adl_info)),
          ' ') AS address,
       CASE
          WHEN i.birth_date = TO_DATE ('9999-12-31') THEN NULL
          ELSE TRUNC (MONTHS_BETWEEN (SYSDATE, i.birth_date) / 12)
       END age,
       CASE
          WHEN SUBSTR (gender, 1, 1) = 'M' THEN 'M'
          WHEN SUBSTR (gender, 1, 1) = 'm' THEN 'M'
          WHEN SUBSTR (gender, 1, 1) = 'F' THEN 'F'
          WHEN SUBSTR (gender, 1, 1) = 'f' THEN 'F'
          ELSE NULL
       END AS gender,
       NULL AS vat_number,
       NULL AS branch,
       NULL AS employees
  FROM idv i
       JOIN cstmr_srgt_key c ON i.idv_id = c.ntrl_key_val
       LEFT JOIN (                                   --> this is QA_address
                  SELECT q.adr_id,
                         q.eff_ts,
                         d.country_id,
                         d.city,
                         d.post_code,
                         d.street,
                         d.unit_nbr,
                         d.adl_info
                    FROM (                           --> this is QA_m  
                          SELECT adr_id, MAX (eff_ts) AS eff_ts
                              FROM addr
                          GROUP BY adr_id) q
                         JOIN addr d
                            ON     q.adr_id = d.adr_id
                               AND q.eff_ts = d.eff_ts) b
          ON i.adr_id = b.adr_id
       LEFT JOIN country ctr ON ctr.country_id = b.country_id
 WHERE     src_stm_id = 100
       AND i.end_ts = '9999-12-31 23:59:59.999999000'
       AND i.del_ind = 'N';