Oracle 18c

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CREATE TABLE Material( name, price, origin_country ) AS
SELECT 'M1', 1, 'Place1' FROM DUAL UNION ALL
SELECT 'M2', 2, 'Place2' FROM DUAL UNION ALL
SELECT 'M3', 3, 'Place3' FROM DUAL;
3 rows affected

CREATE TABLE Product (name, price) AS
SELECT 'P123', 10 FROM DUAL UNION ALL
SELECT 'P13',   8 FROM DUAL UNION ALL
SELECT 'P223',  5 FROM DUAL;
3 rows affected

CREATE TABLE Quantities (productName, materialName, quantity) AS
SELECT 'P123', 'M1', 1 FROM DUAL UNION ALL
SELECT 'P123', 'M2', 1 FROM DUAL UNION ALL
SELECT 'P123', 'M3', 1 FROM DUAL UNION ALL
SELECT 'P13',  'M1', 1 FROM DUAL UNION ALL
SELECT 'P13',  'M3', 1 FROM DUAL UNION ALL
SELECT 'P223', 'M2', 1 FROM DUAL UNION ALL
SELECT 'P223', 'M2', 1 FROM DUAL UNION ALL
SELECT 'P223', 'M3', 1 FROM DUAL;
8 rows affected

SELECT M.*,
       P.name AS ProductName,
       p.Price,
       Q.Quantity,
       COUNT( DISTINCT p.ROWID ) OVER ( PARTITION BY m.ROWID ) AS num_products
FROM   Material M
       INNER JOIN Quantities Q
       ON ( m.Name = Q.MaterialName )
       INNER JOIN Product P
       ON ( Q.ProductName = P.Name )
WHERE  p.price <= 20000
ORDER BY num_products DESC
FETCH FIRST ROW WITH TIES;


NAME
PRICE
ORIGIN_COUNTRY
PRODUCTNAME
PRICE
QUANTITY
NUM_PRODUCTS


M3
3
Place3
P123
10
1
3

M3
3
Place3
P223
5
1
3

M3
3
Place3
P13
8
1
3