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CTE in SQL Server 2008: how to calculate subtotals recursively

I have a table where some parts of the car are connected hierarchically, and I also have the cost of manufacturing these parts in each row. This is a simplification of the table:

parentId  Id description qty manufacturingCost costDescripcion
-------- --- ----------- --- ----------------- ---------------
NULL      1  Car          1  100               Assembly the car
NULL      2  Motorcycle   1  100               Assembly the motrocycle
 1       11  Wheel        4   20               Assembly the wheel
11      111  Rim          1   50               Manufacture the rim
11      112  Tire         1   60               Manufacture the tire
 1       12  Door+Window  4   30               Assembly the door and the window
12      121  Door         1   30               Manufacture the door
12      122  Window       2   10               Manufacture the window
 2       11  Wheel        2   15               Assembly the wheel

I need to get all the family tree starting in "Car" and show the total and total costs for each branch. Better explained: the car has 4 wheels, and each wheel has 1 rim and 1 tire, so I have to get 1 car, 4 wheels, 4 tires, 4 wheels. The costs are a bit more complicated: car assembly costs $ 100, but I have to add to this cost, the assembly of 4 wheels (4x20) and the cost of manufacturing 4 wheels (4x50) and 4 tires (4x60), as well as for doors and windows.

This is the expected result:

parentId  Id description qty manufacturingCost   recLevel
-------- --- ----------- --- -----------------   ---------------
NULL       1  Car          1 940 (100+4*130+4*80) 0
 1        11  Wheel        4 130 (20+50+60)       1
 1        12  Door+Window  4 80  (30+30+2*10)     1
12       121  Door         4 30                   2
12       122  Window       8 10                   2
11       111  Rim          4 50                   2
11       112  Tire         4 60                   2

, , , . . CTE, , , , , ?

:

CREATE TABLE #Costs 
(
  parentId int, 
  Id int, 
  description varchar(50),
  qty int, 
  manufacturingCost int,
  costDescripcion varchar(150)
)

INSERT INTO #Costs VALUES (NULL , 1, 'Car', 1, 100, 'Assembly the car')
INSERT INTO #Costs VALUES (NULL , 2, 'Motorcycle', 1, 100, 'Assembly the motrocycle')
INSERT INTO #Costs VALUES (1 , 11, 'Wheel', 4, 20, 'Assembly the wheel')
INSERT INTO #Costs VALUES (11 , 111, 'Rim', 1, 50, 'Manufacture the rim')
INSERT INTO #Costs VALUES (11 , 112, 'Tire', 1, 60, 'Manufacture the tire')
INSERT INTO #Costs VALUES (1 , 12, 'Door+Window', 4, 30, 'Assembly the door and the window')
INSERT INTO #Costs VALUES (12 , 121, 'Door', 1, 30, 'Manufacture the door')
INSERT INTO #Costs VALUES (12 , 122, 'Window', 2, 10, 'Manufacture the window')
INSERT INTO #Costs VALUES (2 , 11, 'Wheel', 2, 15, 'Assembly the wheel')

CTE :

with CTE(parentId, id, description, totalQty, manufacturingCost, recLevel)
as
(
  select c.parentId, c.id, c.description, c.qty, c.manufacturingCost, 0
  from #Costs c
  where c.id = 1

  union all

  select c.parentId, c.id, c.description, c.qty * ct.totalQty, c.manufacturingCost, ct.recLevel + 1
  from #Costs c
  inner join CTE ct on ct.id = c.parentId 
)
select * from CTE

, , , ( ):

parentId  Id description qty manufacturingCost recLevel
-------- --- ----------- --- ----------------- ---------------
NULL       1  Car          1 100                0
 1        11  Wheel        4 20                 1
 1        12  Door+Window  4 30                 1
12       121  Door         4 30                 2
12       122  Window       8 10                 2
11       111  Rim          4 50                 2
11       112  Tire         4 60                 2

, , CTE? , ?

,

+5
1

-

DECLARE @Table TABLE(
        parentId INT,
        Id INT,
        description VARCHAR(50),
        qty FLOAT,
        manufacturingCost FLOAT,
        costDescripcion VARCHAR(50)
)

INSERT INTO @Table SELECT NULL,1,'Car',1,100,'Assembly the car' 
INSERT INTO @Table SELECT NULL,2,'Motorcycle',1,100,'Assembly the motrocycle' 
INSERT INTO @Table SELECT 1,11,'Wheel',4,20,'Assembly the wheel' 
INSERT INTO @Table SELECT 11,111,'Rim',1,50,'Manufacture the rim' 
INSERT INTO @Table SELECT 11,112,'Tire',1,60,'Manufacture the tire' 
INSERT INTO @Table SELECT 1,12,'Door+Window',4,30,'Assembly the door and the window' 
INSERT INTO @Table SELECT 12,121,'Door',1,30,'Manufacture the door' 
INSERT INTO @Table SELECT 12,122,'Window',2,10,'Manufacture the window' 
INSERT INTO @Table SELECT 2,11,'Wheel',2,15,'Assembly the wheel'

;WITH Vals AS (
        SELECT  *,
                qty Level_Qty,
                CAST(id AS VARCHAR(MAX)) + '\' AS [LEVEL]
        FROM    @Table
        WHERE   parentId IS NULL
        UNION ALL
        SELECT  t.*,                
                p.qty * t.qty Level_Qty,
                CAST(p.[LEVEL] AS VARCHAR(MAX))  + CAST(t.id AS VARCHAR(MAX)) + '\' AS [LEVEL]
        FROM    @Table t INNER JOIN
                Vals p  ON  p.Id = t.parentId
)
SELECT  *,
        (SELECT SUM(Level_Qty * manufacturingCost) FROM Vals WHERE [Level] LIKE v.[LEVEL] + '%') / Level_Qty
FROM    Vals v
ORDER BY [LEVEL]

SQL

+7

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