http://www.apache.org/foundation/how-it-works.html
The blockage was based on the fact that we once had an irreconcilable
downgrade bug and seemed to be set up for that again.
What was the code change that caused this problem in 5.1? You have
provided symptoms of the problem. It would be good to understand the
code change that cause this symptom.
The code change was that in 5.1.60 there were new classes and methods
that were added and referred to in the metadata SQL queries. Going
back to the previous version, the metadata queries were still there but
the classes and methods were not, so it caused this failure. In the
10.1 codeline, this means that no new functions or syntax not
compatible with older versions can be added to the queries. Adding the
drop on version change except for read only databases seems the safest
thing here to me. It seems like it will be a long time before we have a
10.2 release, who knows what will go in the 10.1 codeline.
I don't believe that the blocked patches have this defect. Am I wrong?
Again, I am not sure if DERBY-1107 should stop metadata developments.
Wasn't this "issue" present from the beginning?
It is a serious outstanding issue with the handling of metadata
changes. It would be good to see it resolved soon, because it is again
one possibly needing time travel to resolve, but isn't stopping any
metadata changes from going in now.
So, I'm unclear: Are you still blocking metadata changes or are you
satisfied with the analysis done so far by Knut Anders and Dyre? Can we
proceed with metadata checkins provided that:
1) Such patches clearly describe acceptable upgrade behavior
2) Clean upgrade test results accompany the submissions
Regards,
-Rick
