오라클의 다중 LEFT JOIN

Question

안녕하세요 저는 쿼리를 작성하고 있습니다. 두 번째 왼쪽 조인을 추가하면 문제가 발생합니다. - 두 번째 조인을 추가하기 전에 정상적으로 작동합니다. u는 PLZ이 문제를

SELECT u.dept_name AS deptname, u.user_name AS username, 
u.user_id AS userid, u.single_id AS singleid, 
u.email_address AS emailaddress, to_char(m.cur_week_hits) AS empno, 
to_char(m.prev_week_hits) AS mobiletelno,r.role_id , r.role_name 
to_char(m.cur_week_hits - m.prev_week_hits) AS comptelno 
FROM tn_cf_user u 
    LEFT JOIN 
    (
    SELECT 
      SUM (cur_week_hits) AS cur_week_hits, 
      SUM (prev_week_hits) AS prev_week_hits, 
      user_id 
     FROM pp 
     GROUP BY user_id ) m 
    ON u.user_id = m.user_id 

     LEFT JOIN 
     (
     SELECT ur.role_id , rn.role_name , ur.user_id 
      FROM tn_cf_user_role ur , tn_cf_role rn 
      WHERE ur.role_id = rn.role_id 
     ) r, 
    ON u.user_id = r.user_id 

    AND u.single_id IS NOT NULL 
    AND u.user_type IS NULL 

감사

Answer 1

를 해결 할 수 PLZ이 시도 :에 를 두 번째 가입 m.user_id = r.user_id

로 변경