減去2個SQL查詢的輸出

Question

我是一個菜鳥，並試圖獲得兩個查詢輸出之間的差異。每個查詢創建一個列表。查詢列表>查詢B列表。此外，查詢B輸出是查詢A.

查詢A的一個子集：

SELECT first_name, last_name 
FROM users 
WHERE rating <> '6'; 

查詢B：

SELECT DISTINCT first_name, last_name 
FROM users 
JOIN mp_positions 
ON users.id=mp_positions.user_id 
JOIN mps 
ON mps.id=mp_positions.mp_id 
WHERE mps.status_id = '5'; 

任何幫助，將不勝感激。

Answer 1

我不能完全確定你的表的結構的，雖然你可能會想嘗試這樣的事：

SELECT first_name, last_name 
FROM users 
WHERE rating <> '6' 
AND users.id 
NOT IN (SELECT DISTINCT first_name, last_name 
      FROM users 
      JOIN mp_positions 
      ON users.id=mp_positions.user_id 
      JOIN mps ON mps.id=mp_positions.mp_id 
      WHERE mps.status_id = '5' 
); 

Answer 2

我會用EXCEPT從而

-- It returns rows from Query A which "doesn't exist in" Query B 
SELECT first_name, last_name 
FROM users 
WHERE rating <> '6' 

EXCEPT 

SELECT DISTINCT first_name, last_name 
FROM users 
JOIN mp_positions 
ON users.id=mp_positions.user_id 
JOIN mps 
ON mps.id=mp_positions.mp_id 
WHERE mps.status_id = '5'; 

然後

-- It returns rows from Query B which "doesn't exist in" Query A 
SELECT DISTINCT first_name, last_name 
FROM users 
JOIN mp_positions 
ON users.id=mp_positions.user_id 
JOIN mps 
ON mps.id=mp_positions.mp_id 
WHERE mps.status_id = '5' 

EXCEPT 

SELECT first_name, last_name 
FROM users 
WHERE rating <> '6';