sql – 累积前一行的当前行和的值

;WITH cte
AS
(
   SELECT columnB,sum(columnA) asum 
   FROM @t 
   gROUP BY columnB

),cteranked AS
(
   SELECT asum,columnB,ROW_numbER() OVER(ORDER BY columnB) rownum
   FROM cte
) 
SELECT (SELECT SUM(asum) FROM cteranked c2 WHERE c2.rownum <= c1.ROWNUM),columnB
FROM cteranked c1;

这应该给你：

columnA    columnB
3             a
6             b
10            c
15            d

这是a live demo