組合列數據只顯示唯一值

Question

這是我的源表。我想組合列數據並僅顯示唯一的數據。

SQL> SELECT * FROM DUMMY; 

PLAN_CD    PLAN_NM    CLASS 
-------------------- -------------------- ------ 
D01501    DENTAL    AA 
D01501    DENTAL    AB 
D01501    DENTAL    AC 
V01501    VISION    AA 
V01501    VISION    AB 

我想輸出這樣的。

PLAN_CD    PLAN_NM    
-------    -------- 
D01501    DENTAL,AA,AB,AC    
V01501    VISION,AA,AB 

Answer 1

SELECT PLAN_CD, 
     LISTAGG(PLAN_NM, ',') WITHIN GROUP (ORDER BY PLAN_NM) 
    FROM 
    (
    SELECT PLAN_CD, 
      PLAN_NM AS PLAN_NM 
     FROM DUMMY 
    UNION 
    SELECT PLAN_CD, 
      CLASS AS PLAN_NM 
     FROM DUMMY 
    ) 
GROUP BY PLAN_CD 
ORDER BY PLAN_CD;