On Tue, Sep 1, 2026 at 12:13 PM Peter Smith <[email protected]> wrote: > > Each time new EXCEPT rules are proposed in this thread, they come with > a worked examples, but I felt there was still a risk that other > combinations could be broken and go unnoticed. Then, when a > problematic combination is later encountered, we're back to square one > again. > > To help avoid that, I made a matrix of *many* combinations (~300), > covering both inheritance and partitioning. > > Also, TBH I was getting lost keeping track of what "case 1", "case 2", > etc. meant. In this matrix, every case can instead be referred to like > "11x23" — a combo of clauses "11" and "23" (the first digit being the > schema). This makes it easy to refer to any of the 300 combinations > unambiguously. Furthermore, the same combination numbers (e.g. 11x23) > mean the same thing in both the INHERITANCE and PARTITIONING matrices, > so the two can be directly compared. > > PSA the doc containing the matrices, rules, results, diagrams, and a > key for interpreting them. > > My conclusion is that the rules proposed by Shveta ([1] and also > included in the document) are sound; they can be applied to all these > combinations to give unambiguous results. FWIW, my AI checking > confirms the matrix results are consistent. > > Of course, there are more possible variations (e.g. diamond > inheritance shapes), but IMO these 300 test cases give a much more > solid starting point. >
Thanks, Peter, for putting in such a huge effort to work through these cases. I’ll go through them carefully and get back to you. -- Nisha
