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I can’t see see the similarity. SQL join is the categorical fiber product. Tensor product is not a categorical product. It can be related to the product, but no

by eapriv 8y ago

I can’t see see the similarity. SQL join is the categorical fiber product. Tensor product is not a categorical product. It can be related to the product, but not in a trivial way. In particular, I can’t agree with your statement that the tensor product “involves taking all possible pairs of the components of the input data". It’s one way to construct the tensor product, but conceptually it’s not really about that.

lisper 8y ago
> SQL join is the categorical fiber product You are now beyond the limits of my understanding. I never grokked category theory. SQL join is a Cartesian product. The Tensor product is analogous to a Cartesian product except that the inputs and outputs are ordered tuples instead of sets. That's all I was getting at.