Question

I have this very tricky problem and Im trying to figure it out for a while now,

I have this query result set

    SELECT * FROM Orders

    OrderID | OrderAmount | OrderDate | Expiry Date
    1        $100          2008-01-01    2009-12-31
    2        $200          2009-01-01    2010-12-31
    3        $300          2010-01-01    2011-12-31
    4        $3            2010-01-01    2010-06-31
    5        $400          2007-01-01    2009-05-31

Now, how can i break down each order by OrderDate – ExpiryDate daterange per YEAR

I want the result something like this in my RDLC report

    ORDERS CONSUMED PER YEAR    

    OrderID  |  YEAR     |    Consumed Amount
     1         2008           $50
     1         2009           $50
     2         2009           $100
     2         2010           $100
     3         2010           $150
     3         2011           $150  
     4         2010           $3
     5         2007           $160
     5         2008           $160
     5         2009           $80   <---- another tricky part

The computation is base on the term, eq. (2 year term of $300 means $150 per year)

How can i do this in MS-SQL Query?

** I know the title seems incorrect ^^, i just cant find the right title

Edited: added more samples and explanation

Answer 1

If this is SQL Server 2005 or later, you can use a common table expression to recursively build a table of months and use that to calculate the order amount consumed per year.

A few notes:

1. This solution assumes that the time periods are based on whole months. The approach is to determine the amount of the order consumed per month, then multiply that by the number of months in the year. You could modify this to use an amount consumed per day if needed.

2. In the final select, I cast from money to a decimal with higher precision to try and avoid rounding problems. You may have to adjust this to fit your needs, but I’m not sure that you will be able to avoid rounding problems entirely.

3. The results for OrderID 5 don’t match your sample results. This is because the example has 5 months in 2009, not 6.

---

create table #Orders
(
    OrderID int,
    OrderAmount money,
    OrderDate datetime,
    ExpiryDate datetime
)

insert into #Orders values(1, 100, '2008-01-01', '2009-12-31'),
                          (2, 200, '2009-01-01', '2010-12-31'),
                          (3, 300, '2010-01-01', '2011-12-31'),
                          (4, 3,   '2010-01-01', '2010-06-30'),
                          (5, 400, '2007-01-01', '2009-05-31')

;with cte_months
as
(
    select OrderID, OrderDate, year(OrderDate) OrderYear
    from #Orders
    union all
    select m.OrderID, dateadd(month, 1, m.OrderDate), year(dateadd(month, 1, m.OrderDate)) 
    from cte_months m
        inner join #Orders o on m.OrderID = o.OrderID
    where dateadd(month, 1, m.OrderDate) <= o.ExpiryDate
)
select m.OrderId, m.OrderYear, cast(sum(o.MonthlyAmount) as money) as ConsumedAmount
from
(
    select OrderID, cast(OrderAmount as decimal(12,6)) / (datediff(month, orderdate, ExpiryDate) + 1) as MonthlyAmount
    from #Orders
) o inner join cte_months m on o.OrderID = m.OrderID
group by m.OrderID, m.OrderYear

drop table #Orders

And the results:

OrderId     OrderYear   ConsumedAmount
----------- ----------- ---------------------
1           2008        50.00
1           2009        50.00
2           2009        100.00
2           2010        100.00
3           2010        150.00
3           2011        150.00
4           2010        3.00
5           2007        165.5172
5           2008        165.5172
5           2009        68.9655