Question

我有3张桌子（简化）：

-----------Orders--------------------
Id | Total_Price | Customer_Id | Date

--------Order Details---------------------
Id | Order_Id | Product Name | Qty | Value

----Customers------
Id | Name | Address

我使用此查询获取单个客户的总订单价值：

SELECT C.ID, C.NAME , SUM(O.TOTAL_PRICE)
FROM CUSTOMERS C
JOIN ORDERS O ON O.CUSTOMER_ID = C.ID
GROUP BY C.ID, C.NAME

现在，我想构建一个报告，其总订单价值按一系列日期过滤：

SELECT C.ID, C.NAME , SUM(O.TOTAL_PRICE)
FROM CUSTOMERS C
JOIN ORDERS O ON O.CUSTOMER_ID = C.ID
WHERE O.DATE BETWEEN @value1 AND @value2
GROUP BY C.ID, C.NAME

这样可行，但我想选择按客户分组的总订单价值的最后3年总和，这是我想要的结果：

        1Year | 2Year | 3Year | Customer_Name
    ------------------------------------------------- 
        XXX   | YYY   | ZZZZ  | Customer1
        XYX   | YYZ   | ZZTZ  | Customer2
....

我有这个基数：客户表有22.000行订单表有87.000行订购详情600.000

没有具有较长执行时间的temptable，vartable或存储过程是否可行？

在我的报告中，我还要计算按产品客户分组的过去3年的总数量，但这是下一步。有任何想法吗？感谢

Answer 1

您可以使用案例陈述来获得所需的结果。由于你的帖子中有关于如何定义年份范围的含糊不清，我已经遗漏了任何计算以获得那些年末/开始并且只是将变量放入。你可以修改以满足你的需要。

SELECT C.ID
    ,C.NAME
    ,SUM(CASE 
            WHEN o.DATE BETWEEN @year1start
                    AND @year1end
                THEN O.TOTAL_PRICE
            ELSE 0
            END) Year1
    ,SUM(CASE 
            WHEN o.DATE BETWEEN @year2start
                    AND @year2end
                THEN O.TOTAL_PRICE
            ELSE 0
            END) Year2
    ,SUM(CASE 
            WHEN o.DATE BETWEEN @year3start
                    AND @year3end
                THEN O.TOTAL_PRICE
            ELSE 0
            END) Year3
FROM CUSTOMERS C
INNER JOIN ORDERS O ON O.CUSTOMER_ID = C.ID
GROUP BY C.ID
    ,C.NAME

Answer 2

另一种选择是使用pivot语句。我假设您的每个日期范围等于一年（例如2013年，2014年等）如果强烈确定这些年份，那么选择（look at full sqlfiddle example, it has possible solution for your additional question）

是非常漂亮的选择

select
    c.Id, c.Name, c.Address, CostByYear.[2013], CostByYear.[2014], CostByYear.[2015]
from Customers c
left join (
    select
        pt.Customer_Id, isnull(pt.[2013], 0) as [2013], 
        isnull(pt.[2014], 0) as [2014], isnull(pt.[2015], 0) as [2015]
    from (
        select
            o.Customer_Id, year(o.Date) [Year], sum(o.Total_Price) [TotalCost]
        from Orders o
        group by
            o.Customer_Id, year(o.Date)
    ) src
    pivot (
        sum(TotalCost) for [Year] in ([2013], [2014], [2015])
    ) pt
) CostByYear on
    c.Id = CostByYear.Customer_Id
order by
    c.Name

如果年份范围未知并且定义明确，您也可以使用动态创建的查询执行这两种方法（我的和普通答案）。

使用T-SQL构建去年的客户报告

2 个答案: