Bucket Filling SQL-query CTE

U kunt dit in SQL Server 2008 als volgt doen:

declare @Buckets table (ID char(2), FullCapacity int)
declare @Filler table (ID char(2), Filler int)

insert into @Buckets 
select 'B1', 100 union all
select 'B2', 50 union all
select 'B3', 70 

insert into @Filler 
select 'F1', 90 union all
select 'F2', 70 union all
select 'F3', 40 union all
select 'F4', 20


select 
    b.ID, 
    b.FullCapacity,
    case 
        when f.TotalFill < b.RunningTotalCapacity then 0
        when f.TotalFill > b.RunningTotalCapacity + b.FullCapacity then b.FullCapacity
        else f.TotalFill - b.RunningTotalCapacity
    end as CurrentAmount
from
(
    select      
    ID,
    Filler,
    (
        select sum(f2.Filler)
        from @Filler as f2
        where f2.ID <= f.ID
    ) as TotalFill
    from @Filler as f
) as f
cross join 
(
    select 
        ID,
        FullCapacity, 
        (
            select isnull(sum(b2.FullCapacity), 0)
            from @Buckets as b2
            where b2.ID < b.ID
        ) as RunningTotalCapacity
    from @Buckets as b
) as b
order by f.ID, b.ID

U kunt dit doen met behulp van vensterfuncties zoals deze:

SQL Server 2012+

    declare @Buckets table (ID char(2), FullCapacity int)
    declare @Filler table (ID char(2), Filler int)

    insert into @Buckets values
    ('B1', 100),
    ('B2', 50),
    ('B3', 70)

    insert into @Filler values
    ('F1', 90),
    ('F2', 70),
    ('F3', 40),
    ('F4', 20)

    ;with fillerCte as
    (
        select      
            ID,
            Filler,
            sum(Filler) over (order by ID) as TotalFill
        from @Filler
    ), 
    BucketCte as
    (
        select 
            ID,
            FullCapacity,
            sum(FullCapacity) over (order by ID) - FullCapacity as RunningTotalCapacity
        from @Buckets
    )
    select 
        b.ID, 
        b.FullCapacity,
        case 
            when f.TotalFill < b.RunningTotalCapacity then 0
            when f.TotalFill > b.RunningTotalCapacity + b.FullCapacity then b.FullCapacity
            else f.TotalFill - b.RunningTotalCapacity
        end as CurrentAmount
    from fillerCte as f
    cross join BucketCte as b
    order by f.ID, b.ID