How to generate all possible data combinations in SQL?

Question

I\'m developing a shop web site. I have a database table, ProductOption, that represents the various options that are applicable to a product (Sizes, Colour

Answer 1

in SQLServer you can use CUBE Operator, that return a resultset with all combination... but I don't know if you meaning that...

Hope this helps

Nicola

Answer 2

SELECT PO1.Value, PO2.Value, PO3.Value
FROM ProductOption PO1, ProductOption PO2, ProductOption PO3 
WHERE PO1.ProductOptionGroupID = 1
AND PO2.ProductOptionGroupID = 2
AND PO3.ProductOptionGroupID = 3

Answer 3

Well, you are in kinda of a problem there, specially if you don't know wich groups are attached to wich products ahead of time. It appears to me that you are gonna need two of the biggest things a try to avoid in sql: cursors, and dynamic sql. Before using the following solution, you should take a look at this link The Curse and Blessings of Dynamic SQL. Then, you can try this:

DECLARE @ProductId INT, @Query NVARCHAR(MAX), @ProductOptionGroupId INT
SET @ProductId = 1
SET @Query = ''

DECLARE CC CURSOR FOR
SELECT DISTINCT ProductOptionGroupId
FROM YourTable
WHERE ProductId = @ProductId

OPEN CC
FETCH NEXT FROM CC INTO @ProductOptionGroupId
WHILE @@FETCH_STATUS = 0
BEGIN
    SET @Query = @Query + '(SELECT DISTINCT Value FROM YourTable WHERE ProductOptionGroupId='+CAST(@ProductOptionGroupId AS VARCHAR)+'AND ProductId='+CAST(@ProductId AS VARCHAR)+
                 +') AS Table' + CAST(@ProductOptionGroupId AS VARCHAR)+' CROSS JOIN '

    FETCH NEXT FROM CC INTO @ProductOptionGroupId
END
CLOSE CC
DEALLOCATE CC
SET @Query = 'SELECT * FROM ' + LEFT(@Query,LEN(@Query)-10)

PRINT @Query
EXEC sp_executesql @Query

Let me know how it goes.