Oh b.t.w., I see I didn't mention the view-update problem in databases here. That would be a direct application of category theory. [1] [1] [1] M. Johnson and

Oh b.t.w., I see I didn't mention the view-update problem in databases here. That would be a direct application of category theory. [1] [1] [1] M. Johnson and R. Rosebrugh, Fibrations and universal view updatability, Theoretical Computer Science 388.1, 2007, 109–129.