我有一张包含以下数据的表格:
TradeDate Stock BuySell DayClose
--------------------------------------
10-Dec-12 ABC 1 11
10-Dec-12 ABC 2 12
11-Dec-12 ABC 1 11.5
11-Dec-12 ABC 2 12.5
11-Dec-12 DEF 1 15
11-Dec-12 DEF 2 16
我想查询它的特定日期 11-Dec-2012 以获得以下输出:
Stock Buy Sell Mid Change
--------------------------------------
ABC 11.5 12.5 12.0 0.5
DEF 15 16 15.5
由于 DEF 没有前一个日期的数据,因此 change 应该是空白的。
我创建了以下查询:
Select Stock,
AVG(CASE BuySell WHEN 1 THEN DayClose END) AS 'Buy',
AVG(CASE BuySell WHEN 2 THEN DayClose END) As 'Sell',
Sum(DayClose/2) as 'Mid',
Sum(Change/2) AS Change
FROM (
select t1.Stock, t1.BuySell, t1.DayClose, Sum(t1.DayClose - t2.DayClose) as Change
FROM #myTable as t1 inner join #myTable as t2 on
t1.Stock = t2.Stock
where
t1.TradeDate = '2012-12-11' AND
t2.TradeDate = (SELECT TOP 1 TradeDate FROM #myTable WHERE TradeDate < '2012-12-11' ORDER BY TradeDate DESC)
GROUP BY
t1.Stock, t1.buysell, t1.dayclose ) AS P1 GROUP BY stock
我为此目的创建了一个临时表#mytable:
drop table #mytable
CREATE TABLE #myTable
(
TradeDate datetime,
stock varchar(20),
buysell int,
dayclose decimal(10,2)
)
insert into #mytable values ('10-dec-2012', 'abc' , 1, 11)
insert into #mytable values ('10-dec-2012', 'abc' , 2, 12)
insert into #mytable values ('11-dec-2012', 'abc' , 1, 11.5)
insert into #mytable values ('11-dec-2012', 'abc' , 2, 12.5)
insert into #mytable values ('11-dec-2012', 'def' , 1, 15)
insert into #mytable values ('11-dec-2012', 'def' , 2, 16)
但我无法获得所需的输出,而是获得
Stock Buy Sell Mid Change
--------------------------------------------------------------
abc 11.500000 12.500000 12.00000 1.00
有人可以告诉我哪里出错了。我好像迷路了。
谢谢,莫妮卡