a tricky query

Hello

I have a table: myTable(#Product_ID, #Month, Value), where Product_ID and Month are the PK columns. I would like to retrieve all the rows from Month 10 to Month 12, if-and-only-if all the Values are the same (and not NULL).

Example:

(Cod01, 10, 456), (Cod01, 11, 456), (Cod01, 12, 456) <-- Would pass
(Cod02, 10, 1234), (Cod02, 11, 1234), (Cod02, 12, 1234) <-- Would pass

(Cod03, 10, 345), (Cod03, 11, 1677), (Cod03, 12, 981) <-- Would not pass

How can I accomplish that?

Thanks a lot.select myTable.Product_ID
, myTable.Month
, myTable.Value
from myTable
inner
join (
select Product_ID
from myTable
where Month between 10 and 12
group
by Product_ID
having count(distinct Value)
= count(*)
) as these
on these.Product_ID = myTable.Product_ID
where myTable.Month between 10 and 12|||Declare @.monthStart int
Declare @.monthEnd int

Set @.monthStart = 10
Set @.monthEnd = 12

Select myTable.* from myTable
INNER JOIN
(
Select Product_ID from myTable
where [month] between @.monthStart and @.monthEnd
Group by Product_ID, [Value]
having count(Product_ID) = ((@.monthEnd-@.monthStart)+1)
) this ON this.Product_ID= myTable.Product_ID

-------------------