Question

I have following table

ID | Group      | Type         | Product
1    Dairy         Milk           Fresh Milk
2    Dairy         Butter         Butter Cream
3    Beverage      Coke           Coca cola
4    Beverage      Diet           Dew
5    Beverage      Juice          Fresh Juice

I need following output/query result:

ID | Group      | Type         | Product
1    Dairy             
1                 Milk           Fresh Milk
2                 Butter         Butter Cream
2    Beverage      
1                Coke            Coca cola
2                Diet            Dew
3                Juice           Fresh Juice

For above sample a hard coded script can do the job but I look for a dynamic script for any number of groups. I do not have any idea how it can be done so, I do not have a sample query yet. I need ideas, examples that at least give me an idea. PIVOT looks a close option but does not looks to be fully fit for this case.

Answer 1

Here’s a possible way. It basically unions the “Group-Headers” and the “Group-Items”. The difficulty was to order them correctly.

WITH CTE AS
(
  SELECT ID,[Group],Type,Product,
    ROW_NUMBER() OVER (PARTITION BY [Group] Order By ID)AS RN
  FROM Drink
)
SELECT ID,[Group],Type,Product
FROM(
   SELECT RN AS ID,[Group],[Id]AS OriginalId,'' As Type,'' As Product, 0 AS RN, 'Group' As RowType
   FROM CTE WHERE RN = 1
   UNION ALL
   SELECT RN AS ID,'' AS [Group],[Id]AS OriginalId,Type,Product, RN, 'Item' As RowType
   FROM CTE
)X
ORDER BY  OriginalId ASC
, CASE WHEN RowType='Group' THEN 0 ELSE 1 END ASC
, RN ASC

Here’s a demo-fiddle: http://sqlfiddle.com/#!6/ed6ca/2/0