Product:
  relations:
    LinkedTo:
      class: Product
      local: product1_id
      foreign: product2_id
      refClass: Product__Product
      foreignAlias: LinkedWith  
        
Product__Product:
  columns:
    product1_id:
      type: integer
      primary: true
    product2_id:
      type: integer
      primary: true
  relations:
    Product1:
      class: Product
      local: product1_id
      onDelete: CASCADE
    Product2:
      class: Product
      local: product2_id
      onDelete: CASCADE