sql-server-2005 – 从稀疏填充的数据库表中生成每天一分钟的行
发布时间:2021-03-07 10:04:59 所属栏目:编程 来源:网络整理
导读:我有一个表填充了在当天(基本上)随机点插入的带时间戳的行. 我需要生成每分钟1行的运行总计(因此,对于一天,总会有正好24 * 60行),例如 Date Quantity Running Total2009-10-29 06:30 1 12009-10-29 06:31 5 62009-10-29 06:32 10 16 2009-10-29 06:33 11 27 2
我有一个表填充了在当天(基本上)随机点插入的带时间戳的行. 我需要生成每分钟1行的运行总计(因此,对于一天,总会有正好24 * 60行),例如 Date Quantity Running Total 2009-10-29 06:30 1 1 2009-10-29 06:31 5 6 2009-10-29 06:32 10 16 2009-10-29 06:33 11 27 2009-10-29 06:34 22 49 … 有关最佳方法的任何想法吗? 我的最终解决方案(或多或少). 实际情况是这样的.我有两个表,其中包含与Fills表有1:n关系的Orders. 我需要在交易日显示每分钟的运行平均价格和累计总额 DECLARE @StartDate AS DATETIME,@EndDate AS DATETIME SET @StartDate = '2009-10-28'; SET @EndDate = '2009-10-29'; -- Generate a Temp Table containing all the dates I'm interested in WITH DateIntervalsCTE AS ( SELECT 0 i,@StartDate AS Date UNION ALL SELECT i + 1,DATEADD(minute,i,@StartDate ) FROM DateIntervalsCTE WHERE DATEADD(minute,@StartDate ) < @EndDate ) SELECT DISTINCT Date INTO #Dates FROM DateIntervalsCTE OPTION (MAXRECURSION 32767); SELECT d.Date,mo3.symbol,ISNULL(SUM(mf.Quantity),0) AS CumulativeTotal,ROUND(ISNULL(SUM(mf.Quantity * mf.Price)/SUM(mf.Quantity),0),4) AS AveragePrice FROM #Dates AS d CROSS JOIN ( SELECT DISTINCT mo2.Symbol,mo2.OrderID FROM Orders AS mo2 INNER JOIN Fills AS mf2 ON mo2.OrderID = mf2.OrderID WHERE CONVERT(DATETIME,CONVERT(CHAR(10),mf2.FillDate,101)) = @StartDate ) AS mo3 LEFT JOIN Fills AS mf ON mo3.OrderID = mf.OrderID AND CONVERT(DATETIME,CONVERT(CHAR(16),mf.FillDate,120)) < = d.Date WHERE d.Date >= DATEADD(mi,390,@StartDate) -- 06:30 AND d.Date <= DATEADD(mi,780,@StartDate) -- 13:00 GROUP BY d.Date,mo3.symbol ORDER BY mo3.Symbol,d.Date 我还没有完成我的所有测试,但这看起来像诀窍,谢谢你的帮助! 解决方法确保日期列上有索引,性能应该合理.SELECT t.Date,COUNT(*) AS Quantity,(SELECT COUNT(*) FROM Table WHERE Date < t.Date) AS RunningTotal FROM Table t GROUP BY t.Date 获取每分钟填充一行的表可以非常快速地完成,如下所示: DECLARE @StartDate smalldatetime DECLARE @EndDate smalldatetime SET @StartDate = '1 jan 2009' --MIN(TimeStamp) FROM Table SET @EndDate = '2 jan 2009' --MAX(TimeStamp) FROM Table SET @StartDate = DATEADD(minute,-DATEPART(minute,@StartDate),@StartDate) SET @EndDate = DATEADD(minute,@EndDate),@EndDate) ; WITH DateIntervalsCTE AS ( SELECT 0 i,@startdate AS Date UNION ALL SELECT i + 1,@startdate ) FROM DateIntervalsCTE WHERE DATEADD(minute,@startdate ) <= @enddate ) SELECT DISTINCT Date FROM DateIntervalsCTE OPTION (MAXRECURSION 32767); 只要你需要<由于递归限制,大约22天的数据. 现在你需要的是将两者合并,使用临时表来保存数据似乎是最快的 DECLARE @StartDate smalldatetime DECLARE @EndDate smalldatetime DECLARE @t TABLE (Date smalldatetime,Quantity int,RunningTotal int) SET @StartDate = '1 jan 2009' --MIN(TimeStamp) FROM Table SET @EndDate = '2 jan 2009' --MAX(TimeStamp) FROM Table SET @StartDate = DATEADD(minute,@startdate ) <= @enddate ) INSERT INTO @t (Date) SELECT DISTINCT Date FROM DateIntervalsCTE OPTION (MAXRECURSION 32767); UPDATE t SET Quantity = (SELECT COUNT(d.TimeStamp) FROM Table d WHERE Date = t.date) from @t t update t2 set runningtotal = (SELECT SUM(Quantity) FROM @t WHERE date <= t2.date) from @t t2 select * from @t (编辑:广西网) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |
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