ZODB3

ZODB3 (Zope Object Database) provides an object-oriented database for Python that provides a high-degree of transparency.

Applications can take advantage of object database features with few, if any, changes to application logic. ZODB includes features such as a plugable storage interface, rich transaction support, and undo.

What is new in this release:

• Enforced usage of bytes for '_p_serial' of persistent objects (fixes compatibility with recent persistent releases).

What is new in version 3.10.5:

• Conflict resolution failed when state included cross-database persistent references with classes that couldn't be imported.

What is new in version 3.10.4:

• Conflict resolution failed when state included persistent references with classes that couldn't be imported.

What is new in version 3.10.3:

• Bugs Fixed:
• "activity monitor not updated for subconnections when connection returned to pool"
• https://bugs.launchpad.net/zodb/+bug/737198
• "Blob temp file get's removed before it should", https://bugs.launchpad.net/zodb/+bug/595378
• A way this to happen is that a transaction is aborted after the commit process has started. I don't know how this would happen in the wild.
• In 3.10.3, the ZEO tpc_abort call to the server is changed to be synchronous, which should address this case. Maybe there's another case.
• Performance enhancements:
• Improved ZEO client cache implementation to make it less likely to evict objects that are being used.
• Small (possibly negligable) reduction in CPU in ZEO storage servers to service object loads and in networking code.

What is new in version 3.10.1:

• Bugs Fixed:
• When a transaction rolled back a savepoint after adding objects and subsequently added more objects and committed, an error could be raised "ValueError: A different object already has the same oid" causing the transaction to fail. Worse, this could leave a database in a state where subsequent transactions in the same process would fail.
• https://bugs.launchpad.net/zodb/+bug/665452
• Unix domain sockets didn't work for ZEO (since the addition of IPv6 support). https://bugs.launchpad.net/zodb/+bug/663259
• Removed a missfeature that can cause performance problems when using an external garbage collector with ZEO. When objects were deleted from a storage, invalidations were sent to clients. This makes no sense. It's wildly unlikely that the other connections/clients have copies of the garbage. In normal storage garbage collection, we don't send invalidations. There's no reason to send them when an external garbage collector is used.
• ZEO client cache simulation misshandled invalidations causing incorrect statistics and errors.

What is new in version 3.10.0 Beta 8:

• Bugs fixed:
• On some systems, using an empty string in a server address of a ZEO client led to a socket error. Now, ZEO clients treat '' as an alias for 'localhost'.
• When a pool timeout was specified for a database and old connections were removed due to timing out, an error occured due to a bug in the connection cleanup logic.
• When mulri-database connections were no longer used and cleaned up, their subconnections weren't cleaned up properly.
• Changes to suppprt IPv6 broke a fix for a problem on Mac OS X that could cause a server to stop accepting connections.

What is new in version 3.9.7:

• Bugs Fixed:
• Changes in way that garbage collection treats dictionaries in Python 2.7 broke the object/connection cache implementation. (https://bugs.launchpad.net/zodb/+bug/641481)
• Python 2.7 wasn't officially supported, but we were releasing binaries for it, so ...Logrotation/repoening via a SIGUSR2 signal wasn't implemented. (https://bugs.launchpad.net/zodb/+bug/143600)
• When using multi-databases, cache-management operations on a connection, cacheMinimize and cacheGC, weren't applied to subconnections.

What is new in version 3.10.0 Beta 7:

• Bugs fixed:
• ZEO didn't work with IPv6 addrsses. Added IPv6 support contributed by Martin v. Lowis.
• Changes in way that garage collection treats dictionaries in Python 2.7 broke the object/connection cache implementation. (https://bugs.launchpad.net/zodb/+bug/641481)
• A file storage bug could cause ZEO clients to have incorrect information about current object revisions after reconnecting to a database server.
• Updated the 'repozo --kill-old-on-full' option to remove any '.index' files corresponding to backups being removed.
• When objects were added in savepoints and either the savepoint was rolled back (https://bugs.launchpad.net/zodb/+bug/143560) or the transaction was aborted (https://mail.zope.org/pipermail/zodb-dev/2010-June/013488.html) The objects' _p_oid and _p_jar variables weren't cleared, leading to surprizing errors.
• ZEO extension methods failed when a client reconnected to a storage. (https://bugs.launchpad.net/zodb/+bug/143344)
• Objects added in transactions that were later aborted could have _p_changed still set (https://bugs.launchpad.net/zodb/+bug/615758).
• Clarified the return Value for lastTransaction in the case when there aren't any transactions. Now a string of 8 nulls (aka "z64") is specified.
• When using multi-databases, cache-management operations on a connection, cacheMinimize and cacheGC, weren't applied to subconnections.
• Setting _p_changed on a blob wo actually writing anything caused an error. (https://bugs.launchpad.net/zodb/+bug/440234)
• The verbose mode of the fstest was broken. (https://bugs.launchpad.net/zodb/+bug/475996)
• Object ids created in a savepoint that is rolled back wren't being reused. (https://bugs.launchpad.net/zodb/+bug/588389)
• Logrotation/repoening via a SIGUSR2 signal wasn't implemented. (https://bugs.launchpad.net/zodb/+bug/143600) (Untested on windows.)

What is new in version 3.10.0 Beta 6:

• Process exits or database closes could cause ZEO caches to have incorrect data due to a problem in the way invalidations were processed.
• Database connections didn't invalidate cache entries when conflict errors were raised in response to checkCurrentSerialInTransaction errors. Normally, this shouldn't be a problem, since there should be pending invalidations for these oids which will cause the object to be invalidated. There have been issues with ZEO persistent cache management that have caused out of date data to remain in the cache. (It's possible that the last of these were addressed in the 3.10.0b5.) Invalidating read data when there is a conflict error provides some extra insurance.
• The interface, ZODB.interfaces.IStorage was incorrect. The store method should never return a sequence of oid and serial pairs.

Requirements:

• Python