如何添加兩個被聯合在一起的查詢

Question

我試圖通過人一起添加兩個組，這是我的代碼：

SELECT VISITOR,COUNT(VISITOR) 
FROM ENGLAND 
WHERE TIER = 1 AND SEASON >= 1980 
GROUP BY VISITOR 
UNION 
SELECT HOME,COUNT(HOME) 
FROM ENGLAND 
WHERE TIER = 1 AND SEASON >= 1980 
GROUP BY HOME; 

這裏是輸出的一部分

AFC Bournemouth 37 
AFC Bournemouth 38 

和問題是我怎麼能夠使輸出看起來像

AFC Bournemouth 75 

（這意味着增加遊戲的國內和訪問者NUM在一起）

Answer 1

計算機科學中的所有問題都可以通過另一個間接層面來解決。
- David Wheeler

您想同時添加相同名稱的值嗎？只要使用SUM（）和GROUP BY：

SELECT Name, SUM(Games) AS Games 
FROM (SELECT Visitor AS Name, COUNT(*) AS Games 
     FROM England 
     WHERE Tier = 1 AND Season >= 1980 
     GROUP BY Visitor 
     UNION ALL 
     SELECT Home, COUNT(*) 
     FROM England 
     WHERE Tier = 1 AND Season >= 1980 
     GROUP BY Home) 
GROUP BY Name; 

（UNION沒有ALL會刪除重複的，如果有相同數量的本地和訪問者遊戲可能出現這種情況）

---

另外，帶原始表的形式，讓他們都來一次彙總值：

SELECT Name, COUNT(*) AS Games 
FROM (SELECT Visitor AS Name 
     FROM England 
     WHERE Tier >= 1 AND Season >= 1980 
     UNION ALL 
     SELECT Home 
     FROM England 
     WHERE Tier >= 1 AND Season >= 1980) 
GROUP BY Name;