SQL Recursive CTE 'where-used' / BOM explo

Question

What I'm trying to do simply is for an item from the BOM table (Bill of Materials) get it's related components/products from BOMVERSION and then for those related components/products get their related components and products etc. down to 7 levels. I then want to pivot the results so that the related items get put in columns 0, 1, 2, 3, 4, 5, 6, 7

Please see attached example data and code. I'm using dynamics AX 2012 R2 but this example could be applied to any system that uses materials/products. I cannot get my query to complete however (I know I don't have dataareaid and partition I've left out for simplicity). the relationship is an itemid from BOM table is related to itemid in BOMVERSION through BOMID.

UPDATE : I've simplified data etc. to make as simple/clear as possible, so materials wood, metal, glass can go into making various products and materials themselves, and can be combined to make products or materials. Therefore I want to start with a base component, then explode the relationships out by levels.

DDL + DML:

    USE tempdb;

IF OBJECT_ID('tempdb..#BOM') IS NOT NULL
    DROP TABLE #BOM;

CREATE TABLE #BOM
    (
      ITEMID NVARCHAR(10) ,
      BOMID NVARCHAR(10) ,
      MATERIALNAME NVARCHAR(10)
    );

INSERT  INTO #BOM
VALUES  ( N'113621', -- ITEMID - nvarchar(10)
          N'1',  -- BOMID - nvarchar(10)
          N'Wood'  -- MATERIALNAME - nvarchar(10)
          );

INSERT  INTO #BOM
VALUES  ( N'234517', -- ITEMID - nvarchar(10)
          N'2',  -- BOMID - nvarchar(10)
          N'Metal'  -- MATERIALNAME - nvarchar(10)
          );

INSERT  INTO #BOM
VALUES  ( N'378654', -- ITEMID - nvarchar(10)
          N'3',  -- BOMID - nvarchar(10)
          N'Glass'  -- MATERIALNAME - nvarchar(10)
          );

IF OBJECT_ID('tempdb..#BOMVERSION') IS NOT NULL
    DROP TABLE #BOMVERSION;

CREATE TABLE #BOMVERSION
    (
      ITEMID NVARCHAR(10) ,
      BOMID NVARCHAR(10) ,
      NAME NVARCHAR(20)
    );

INSERT  INTO #BOMVERSION
VALUES  ( N'113477', -- ITEMID - nvarchar(10)
          N'1', -- BOMID - nvarchar(10)
          N'Oak'  -- NAME - nvarchar(10)
          );

INSERT  INTO #BOMVERSION
VALUES  ( N'113608', -- ITEMID - nvarchar(10)
          N'1', -- BOMID - nvarchar(10)
          N'Pine'  -- NAME - nvarchar(10)
          );

INSERT  INTO #BOMVERSION
VALUES  ( N'113622', -- ITEMID - nvarchar(10)
          N'1', -- BOMID - nvarchar(10)
          N'Wood Table'  -- NAME - nvarchar(10)
          );

INSERT  INTO #BOMVERSION
VALUES  ( N'113683', -- ITEMID - nvarchar(10)
          N'2', -- BOMID - nvarchar(10)
          N'Aluminium'  -- NAME - nvarchar(10)
          );

INSERT  INTO #BOMVERSION
VALUES  ( N'113689', -- ITEMID - nvarchar(10)
          N'2', -- BOMID - nvarchar(10)
          N'Steel'  -- NAME - nvarchar(10)
          );

INSERT  INTO #BOMVERSION
VALUES  ( N'113693', -- ITEMID - nvarchar(10)
          N'2', -- BOMID - nvarchar(10)
          N'Metal table'  -- NAME - nvarchar(10)
          );

INSERT  INTO #BOMVERSION
VALUES  ( N'113694', -- ITEMID - nvarchar(10)
          N'3', -- BOMID - nvarchar(10)
          N'Glass'  -- NAME - nvarchar(10)
          );

INSERT  INTO #BOMVERSION
VALUES  ( N'113695', -- ITEMID - nvarchar(10)
          N'3', -- BOMID - nvarchar(10)
          N'Glass BookCase'  -- NAME - nvarchar(10)
          );

--Query

WITH    BOM1
          AS ( SELECT   B.ITEMID AS BITEMID ,
                        BV.ITEMID AS BVITEMID ,
                        B.MATERIALNAME ,
                        B.BOMID
               FROM     #BOM AS B
                        JOIN #BOMVERSION AS BV ON BV.BOMID = B.BOMID
             ),
        EXPLODE
          AS ( SELECT   B.BITEMID ,
                        B.MATERIALNAME ,
                        B.BVITEMID ,
                        B.BOMID ,
                        0 AS [Level]
               FROM     BOM1 AS B
               UNION ALL
               SELECT   B.BITEMID ,
                        E.MATERIALNAME ,
                        E.BVITEMID ,
                        E.BOMID ,
                        [E].[Level] + 1
               FROM     EXPLODE AS E
                        JOIN BOM1 AS B ON B.BOMID = E.BOMID
               WHERE    E.Level <= 6   --narrowing levels                   
             )
    SELECT  *
    FROM    EXPLODE PIVOT ( MAX(BVITEMID) FOR Level IN ( [0], [1], [2], [3],
                                                         [4], [5], [6], [7] ) ) AS PVTBOM;

Output to look like

Answer 1

Well this is just to eliminate errors and get results, but I don't know if the results are correct:

WITH    BOM1
          AS ( SELECT   B.ITEMID AS BITEMID ,
                        BV.ITEMID AS BVITEMID ,
                        B.BOMID
               FROM     #BOM AS B
                        JOIN #BOMVERSION AS BV ON BV.BOMID = B.BOMID
             ),
        EXPLODE
          AS ( SELECT   B.BITEMID ,
                        B.BVITEMID ,
                        B.BOMID ,
                        0 AS [Level]
               FROM     BOM1 AS B
               UNION ALL
               SELECT   B.BITEMID ,
                        E.BVITEMID ,
                        E.BOMID ,
                        [E].[Level] + 1
               FROM     EXPLODE AS E
                        JOIN BOM1 AS B ON B.BOMID = E.BOMID
               WHERE e.Level <= 6   --narrowing levels                   
             )


    SELECT  *
    FROM    EXPLODE PIVOT ( MAX(BVITEMID) FOR Level IN ( [0], [1], [2], [3],
                                                         [4], [5], [6], [7] ) ) AS PVTBOM

You had maxrecursion = 7 - this is not the place to narrow the levels. Levels are narrowed inside recursive part in CTE.

I suspect your recursion is not well organized, so can you simplify your test data? Just leave several rows and show the expected output.

EDIT1:

WITH    p AS ( SELECT   *
               FROM     ( SELECT    itemid ,
                                    bomid ,
                                    ROW_NUMBER() OVER ( PARTITION BY Bomid ORDER BY itemid ) rn
                          FROM      #BOMVERSION
                        ) t PIVOT ( MAX(itemid) FOR rn IN ( [1], [2], [3], [4],
                                                            [5], [6], [7], [8] ) ) p
             )
    SELECT  *
    FROM    #bom b
JOIN p ON b.bomid = p.bomid    

EDIT2:

;WITH    cte
          AS ( SELECT   b.itemid AS originalitem ,
                        b.bomid AS originalbom ,
                        b.bomid ,
                        bv.itemid AS parent ,
                        0 AS level
               FROM     #BOM b
                        JOIN #BOMVERSION bv ON bv.bomid = b.bomid
               UNION ALL
               SELECT   c.originalitem ,
                        c.originalbom ,
                        b.bomid ,
                        bv.itemid ,
                        c.level + 1
               FROM     cte c
                        JOIN #BOM b ON c.parent = b.itemid
                        JOIN #BOMVERSION bv ON bv.bomid = b.bomid
               WHERE    c.level <= 6
             ),
        tree
          AS ( SELECT   originalitem ,
                        originalbom ,
                        parent ,
                        level
               FROM     cte
             )
    SELECT  *
    FROM    tree PIVOT ( MAX(parent) FOR level IN ( [0], [1], [2], [3], [4], [5], [6], [7] ) ) AS p