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  1. SELECT DISTINCT p.productname, pv1.vendorid
  2. FROM products p INNER JOIN product_vendors pv1 ON p.productnumber = pv1.productnumber
  3. INNER JOIN product_vendors pv2 ON pv1.vendorid = pv2.vendorid
  4. AND pv1.productnumber<>pv2.productnumber
  5. ORDER BY productname;
  6.