I have this two Data Extensions and the ProductCode is the same as Product1, Product2, Product3, Product4...Product10

The problem is that there is some Products in Product1, Product2...Product10 Data Extension that don't exist in ProductCode Data extension and I want to create a list with this products but I can't think of any way of doing that.

I tried to create 10 queries joining the Second Data Extension on Product1 = ProductCode and use the union function but I don't think that's the best way.

I hope this makes sense.
If you have better ways of doing this please share

[![enter image description here][1]][1]

[![enter image description here][2]][2]

  [1]: https://i.sstatic.net/HnclC.png
  [2]: https://i.sstatic.net/wjn6Q.png