SQL Server 2019

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create table rit (ritid int, loadfactor int)
insert into rit (ritid, loadfactor) values (1, 5)

select * from rit


ritid
loadfactor


1
5


select r.ritid, r.loadfactor, cvirtual.ProductSequence
from   rit r
outer apply ( select top(r.loadfactor)
                     RitID,
                     CarID,
                     row_number() over (partition by RitID order by RitID) as ProductSequence
              from ( values(r.RitID, 1),
                           (r.RitID, 2),
                           (r.RitID, 3),
                           (r.RitID, 4),
                           (r.RitID, 5),
                           (r.RitID, 6),
                           (r.RitID, 7),
                           (r.RitID, 8),
                           (r.RitID, 9),
                           (r.RitID, 10),
                           (r.RitID, 11)
                   ) as X(RitID, CarId)
              --where  c.CarID is null
            ) cvirtual --on r.RitID = cvirtual.RitID


ritid
loadfactor
ProductSequence


1
5
1

1
5
2

1
5
3

1
5
4

1
5
5


update rit
set loadfactor = 3
1 rows affected

select r.ritid, r.loadfactor, cvirtual.ProductSequence
from   rit r
outer apply ( select top(r.loadfactor)
                     RitID,
                     CarID,
                     row_number() over (partition by RitID order by RitID) as ProductSequence
              from ( values(r.RitID, 1),
                           (r.RitID, 2),
                           (r.RitID, 3),
                           (r.RitID, 4),
                           (r.RitID, 5),
                           (r.RitID, 6),
                           (r.RitID, 7),
                           (r.RitID, 8),
                           (r.RitID, 9),
                           (r.RitID, 10),
                           (r.RitID, 11)
                   ) as X(RitID, CarId)
              --where  c.CarID is null
            ) cvirtual --on r.RitID = cvirtual.RitID


ritid
loadfactor
ProductSequence


1
3
1

1
3
2

1
3
3