[ZODB-Dev] conflict resolution for PersistentList

[Tim Peters]

[Chris McDonough]
> ...
> Various "BTrees" data structures also provide mapping-like features, and
> they provide a bit of built-in conflict resolution, which is based on a
> hardcoded policy.  But what actually would happen if these items were
> BTree-variant objects depends on the state stored in the database when
> these two transactions commit simultaneously (I couldn't tell you what I
> think the actual effect would be without seeing the original database
> state).  In any case, a set of rules will be consulted.  These are
> documented in the BTrees code, and also outlined by Tim at
> http://mail.zope.org/pipermail/zodb-dev/2004-February/006768.html .  I
> think he also added this to some set of semi-official ZODB docs
> someplace, but I can't find that at the moment.

It's in the seemingly stillborn ZODBTopics Wiki:

    http://zope.org/Wikis/ZODB/ZODBTopics

under node BTreeConflictResolution:

    http://zope.org/Wikis/ZODB/BTreeConflictResolution

The writeup there explains a bit more than the union of my earlier email and
the code comments.