SQL計算運行

Question

我在我的Access數據庫中運行SQL查詢以累積我在每條記錄之後運行的距離。

我用下面的代碼來計算運行總計：

SELECT a.run, a.year, a.date, a.distance, round((SELECT SUM(b.distance) 
         FROM vwAllCast b 
         WHERE b.run <= a.run),1) AS AccDistance 
FROM vwAllCast AS a 
ORDER BY a.run DESC; 

此代碼返回所有的記錄總結在AccDistance所有距離。現在，我想每年都重新進行一次積累。有沒有人有一個想法如何實現？

Answer 1

一樣的Piyush說，我覺得這樣的事情應該工作：

SELECT a.run, a.year, a.date, a.distance, round((SELECT SUM(b.distance) 
         FROM vwAllCast b 
         WHERE b.run <= a.run and a.year = b.year),1) AS AccDistance 
FROM vwAllCast AS a 
ORDER BY a.run DESC; 

Answer 2

自由可能比相關子查詢更快加入+組

SELECT a.run, a.year, a.date, a.distance, SUM(b.distance) 
FROM vwAllCast AS a 
JOIN vwAllCast b on b.run <= a.run AND b.year = a.year 
GROUP BY a.run, a.year, a.date, a.distance 
ORDER BY a.run DESC