1SELECT2t.OrderYear,3t.OrderMonth,4t.TotalDue,5SUM(t.TotalDue)OVER(ORDERBYt.OrderYear, t.OrderMonth ROWSBETWEENUNBOUNDED PRECEDINGANDCURRENTROW)AS'RunningTotal'6FROM7(8SELECT9YEAR(OrderDate)AS'OrderYear',10MONTH(OrderDate)AS'OrderMonth',11SalesPersonID,12TotalDue13FROMSales.SalesOrderHeader14)A...
讲解一下:以FIRST_VALUE为例,其实就是返回这个分组中某个范围里的第一行,而那个名叫ROWS的window frame unit,我的理解就是继续缩小范围,比如ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW意思就是把范围定在分组的开始到当前行,ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING就是把范围定在当前行到分组的结束。
SUM(sale_price) OVER ( ORDER BY sale_price range BETWEEN UNBOUNDED PRECEDING and current row ) AS current_sum FROM Product; 注:默认框架为range BETWEEN UNBOUNDED PRECEDING and current row,row和range的区别是rows按照行进行计算,如当求第一行的时候,求和为第一行-第一行,当求第二行的时候,求和为第...
窗口函数sum(sum(ws_sales_price)) over (partition by ws_item_sk order by d_date rows between unbounded preceding and current row)的含义是:以ws_item_sk为分组,以d_date为顺序,计算从开始截止到当天累计销售额。 三. Window子句 通过这个语句,细心的读者可以发现,窗口函数基本都是相同的格式partition by...
How can I convert from SQL Server ORDER BY [Date] ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW to LinQ Query? I have a SQL query and want to convert it to LINQ. It would be great if some experienced people could help. CREATE TABLE [dbo].[tbl_payment]( [Id] [int] IDENTITY(1,...
AND CURRENT ROW) AS lo, first_value(hi) IGNORE NULLS OVER ( ORDER BY id DESC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING) AS hi FROM trx 有很多关键词!但本质都是一样的。从任何给定的“当前”行中,我们查看所有“之前的值”(ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW),但忽略所有空值...
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW就是取从最开始到当前这一条数据,row_number()这个函数就是这样取的 ROWS BETWEEN 2 PRECEDING AND 2 FOLLOWING代表取前面两条和后面两条数据参与计算,比如计算前后五天内的移动平均就可以这样算. RangeFrame:以当前值为锚点进行计算。比如RANGE BETWEEN 20 PRECEDING...
-＞ SELECT yearweek(payment_date) payment_week, -＞ sum(amount) week_total, -＞ avg(sum(amount)) -＞ over (order by yearweek(payment_date) -＞ rows between 1 preceding and 1 following) rolling_3wk_avg -＞ FROM payment -＞ GROUP BY yearweek(payment_date...
Returns the result row immediately preceding the current row, and decrements the current row to the row returned. IfFETCH PRIORis the first fetch against a cursor, no row is returned and the cursor is left positioned before the first row. ...