Group rows into sets of 5

Question

TableA

Col1
----------
1
2
3
4....all the way to 27

I want to add a second column that assigns a number to groups of 5.

Results

Answer 1

You can use this:

;WITH CTE AS
(
    SELECT col1,
           RN = ROW_NUMBER() OVER(ORDER BY col1)
    FROM TableA
)
SELECT col1, (RN-1)/5+1 col2
FROM CTE;

In your sample data, col1 is a correlative without gaps, so you could use it directly (if it's an INT) without using ROW_NUMBER(). But in the case that it isn't, then this answer works too. Here is the modified sqlfiddle.