比方说,我有一个表ClientClde,就像这样：
ClientName,TradeDate,Quantity
我想在Oracle PLsql中创建一个查询,它应该返回如下结果：
(天数来自TradeDate列,Mon = Sum(数量)为Mon,Tue = sum(Quantity)为Tue ……等)
ClientName Mon Tue Wed Thu Fri Sat Sun TotalForWeek ABC 10 15 5 2 4 0 0 34 XYZ 1 1 2 1 2 0 0 7
假设此报告始终具有使其运行一周的条件,是否可以在单个查询中创建此报告？
解决方法
只是简化一下……
SELECT ClientName,SUM(CASE WHEN to_char(TradeDate,'DY')='MON' THEN Quantity ELSE NULL END) AS Mon,'DY')='TUE' THEN Quantity ELSE NULL END) AS Tue,'DY')='WED' THEN Quantity ELSE NULL END) AS Wed,'DY')='THU' THEN Quantity ELSE NULL END) AS Thu,'DY')='FRI' THEN Quantity ELSE NULL END) AS Fri,'DY')='SAT' THEN Quantity ELSE NULL END) AS Sat,'DY')='SUN' THEN Quantity ELSE NULL END) AS Sun,SUM(Quantity) AS TotalForWeek FROM ClientTrade GROUP BY ClientName
