Question

I am working with data that is grouped by item number with counts. Each record with a count > 2 needs to be blown out into individual records and compared at that level to a different set of data.

The data looks like this (It is stuck in this format. This is the only way the customer can send it.):

OwnerNumber ItemCode    ItemNumber  CountOfItems
1234    Item1   Item1-001   3
1234    Item1   Item1-002   1
1234    Item1   Item1-003   2
1234    Item2   Item2-001   1

And I need the data formatted like this (dynamically without hardcoding for value of CountOfItems):

OwnerNumber ItemCode    ItemNumber  
1234    Item1   Item1-001
1234    Item1   Item1-001
1234    Item1   Item1-001
1234    Item1   Item1-002
1234    Item1   Item1-003
1234    Item1   Item1-003
1234    Item2   Item2-001

For some reason I just can’t wrap my head around a clean way to do this (or any way).

Answer 1

You can manage with a Common Table Expression

WITH CTE AS (
    SELECT OwnerNumber,ItemCode,ItemNumber,CountOfItems FROM table

    UNION ALL SELECT OwnerNumber,ItemCode,ItemNumber,CountOfItems-1
    FROM CTE
    WHERE CountOfItems >= 2
)
SELECT OwnerNumber,ItemCode,ItemNumber
FROM CTE
ORDER BY ItemNumber
OPTION (MAXRECURSION 0);

Edit:

Added MAXRECURSION to handle situations where CountOfItems exceeds default max recursions as pointed out by Dev_etter