I just released an update to 3.9 that fixes a BTree bug that was
introduced in ZODB 3.9.0c2. The bug can cause keys to be inaccessible
except through iteration. It only has an impact under specific
situations when deleting items. I recommend that people running 3.9
update to the new release as soon as reasonable. (If you're using ZEO,
this only applies to ZEO clients, but servers.
To determine whether the bug affected you, you can use the checkbtrees
script in the ZODB/scripts package.
I'm working on a repair script but wanted to get the fix out as soon
as possible to prevent further damage.
For more information about ZODB, see the ZODB Wiki:
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