Question

我想要实现以下目标：

    SELECT DISTINCT 
    id AS Col0,
    'constant' AS Col1
    IIF(z < 0, x, 0) AS Col2,
    IIF(z > 0, x, 0) AS Col3,
    SUM(x) OVER(ORDER BY Col2 DESC ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS [Col4]
FROM y
ORDER BY Col2 DESC
OFFSET 0 ROWS
FETCH NEXT 500 ROWS ONLY

我正在尝试制作累积专栏。问题是我想使用表格＆＃39; ORDERBY()动态OVER()但OVER(ORDERBY())不支持基于索引，也不接受Col1作为列。

我该怎么做呢？我可以在代码中轻松地做一些事情，但我更愿意学习如何在纯SQL中执行此操作。

Answer 1

只需将Order By Col2替换为用于创建Col2的表达式

SELECT DISTINCT 
    id AS Col0,
    'constant' AS Col1
    IIF(z < 0, x, 0) AS Col2,
    IIF(z > 0, x, 0) AS Col3,
    SUM(x) OVER(ORDER BY IIF(z > 0, x, 0) DESC ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS [Col4]
FROM y
ORDER BY Col2 DESC
OFFSET 0 ROWS
FETCH NEXT 500 ROWS ONLY

如何在具有现有订单的表上使用OVER（ORDER BY（））？

1 个答案: