Get all possible concatenations

Question

I have a database that I've inherited and need to create a query that generates all possible variations of a SKU. One table has the "base" SKU and the other table has all the SKU modifiers.

Example

Base SKU: MARIN could be modified into

MARINR15 MARINB15 MARING15 MARINR17 MARINB17 MARING17 MARINR19 MARINB19 MARING19 MARINR20 MARINB20 MARING20

Base SKU

ProductID   SKU
----------- ---------------
532         MARIN

SKU Modifiers

ProductID   OptionName           OptionValue              SkuModifier
----------- -------------------- ------------------------ -----------
532         Color                Red                      R
532         Color                Green                    G
532         Color                Blue                     B
532         Size                 17"                      17
532         Size                 15"                      15
532         Size                 19"                      19
532         Size                 20"                      20

Answer 1

You can use a recursive solution (and indeed, this is probably the only viable answer). You'd probably save processing if you had a predifined ordering (because at the moment the only way I can think to do this is text concatenation).

Here is a general solution that should get you your needed results.
Note that this was written and run on DB2 (iSeries) - you may need to adjust it for SQL Server.

WITH Combined(productId, options, combination, level) as (
              SELECT productId, optionName, skuModifier, 1
              FROM #Modifiers
              UNION ALL
              SELECT a.productId, a.options || b.optionName,
                     a.combination || b.skuModifier, a.level + 1
              FROM Combined as a
              JOIN #Modifiers as b
              ON b.productId = a.productId
              AND a.options not like ('%' || b.optionName || '%')),
     Option_Count(productId, count) as (SELECT productId, COUNT(DISTINCT optionName)
                                        FROM #Modifiers
                                        GROUP BY productId)
SELECT a.sku || COALESCE(b.combination, '')
FROM #Base as a
LEFT JOIN (Combined as b
           JOIN Option_Count as c
           ON c.productId = b.productId
           AND c.count = b.level)
ON b.productId = a.productId)

Which yields:

MARIN17R        
MARIN15R        
MARIN19R        
MARIN20R        
MARIN17G        
MARIN15G        
MARIN19G        
MARIN20G        
MARIN17B        
MARIN15B        
MARIN19B        
MARIN20B        
MARINR17        
MARING17        
MARINB17        
MARINR15        
MARING15        
MARINB15        
MARINR19        
MARING19   
MARINB19   
MARINR20   
MARING20   
MARINB20

Personally, though, I think I'd try to get some sort of ordering established - this would at least allow you to knock out dealing with optionName (although in that case you may want to further normalize the tables).
Please note that the CTE Option_Count is being used to restrict results to 'full-length' combinations - permutations where all the options are used, rather than just some of them.

Answer 2

DROP TABLE #Base
DROP TABLE #Modifiers

CREATE TABLE #Base
(
    ProductId int,
    SKU varchar(32)
)

CREATE TABLE #Modifiers
(
    ProductId int,
    OptionName varchar(32),
    OptionValue varchar(32),
    SKUModifier varchar(32)
)

INSERT INTO #Base
SELECT 532, 'MARIN'

INSERT INTO #Modifiers
SELECT 532, 'Color', 'Red', 'R' UNION ALL
SELECT 532, 'Color', 'Green', 'G' UNION ALL
SELECT 532, 'Color', 'Blue', 'B' UNION ALL
SELECT 532, 'Size', '17"', '17' UNION ALL
SELECT 532, 'Size', '15"', '15' UNION ALL
SELECT 532, 'Size', '19"', '19' UNION ALL
SELECT 532, 'Size', '20"', '20'

SELECT B.SKU + M.SKUModifier + M2.SKUModifier FROM #Base B
    JOIN #Modifiers M ON B.ProductId = M.ProductId AND M.OptionName = 'Color'
    JOIN #Modifiers M2 ON B.ProductId = M2.ProductId AND M2.OptionName = 'Size'

Results:

MARINR17
MARING17
MARINB17
MARINR15
MARING15
MARINB15
MARINR19
MARING19
MARINB19
MARINR20
MARING20
MARINB20

Answer 3

SELECT 
  base.sku+color.SkuModifier+size.SkuModifier 
FROM base 
INNER JOIN modifiers as color ON color.OptionName = 'Color'
INNER JOIN modifiers as size ON size.OptionName = 'Size'

You'll probably have to process OptionValue (for instance, removing the " from Size and taking the first letter from Color), but this will get you on the right path.

EDIT -- Thanks for the clarification, I've updated the SQL.