this was the original issue: https://hibernate.atlassian.net/browse/HHH-10152 as it described by gabor it was working in hibernate-4 it's no longer work in hibernate-5. IMHO it's a regression.
since it's not behaves as the previous versions. first of all we don't understand why reject the original issue which clearly describe a regression in hibernate-5. we hope you understand better the code and that's why you wrote this new issue. it seems to me that you still do NOT understand the problem. it has nothing to do with the extra/non-standard mariadb or mysql table type!
could you please reread the original issue too!

this's the reason why we can't migrate to hibernate-5!

thanks.