ConflictError: database conflict error

Question

Can anybody explain me that error - and how I can repair it?

We use:

• Plone 4
• Zope 2.12.19
• ZEO
• zodb-temporary-storage

Error Log

Site Error

An error was encountered while publishing this resource.

Sorry, a site error occurred.

Traceback (innermost last):

Module ZPublisher.Publish, line 239, in publish_module_standard
Module ZPublisher.Publish, line 197, in publish
Module ZPublisher.Publish, line 197, in publish
Module ZPublisher.Publish, line 197, in publish
Module ZPublisher.Publish, line 173, in publish
Module plone.app.linkintegrity.monkey, line 17, in zpublisher_exception_hook_wrapper
Module ZPublisher.Publish, line 135, in publish
Module Zope2.App.startup, line 291, in commit
Module transaction._manager, line 93, in commit
Module transaction._transaction, line 322, in commit
Module transaction._transaction, line 419, in _commitResources
Module ZODB.Connection, line 767, in tpc_vote
Module ZEO.ClientStorage, line 1068, in tpc_vote
Module ZEO.ClientStorage, line 905, in _check_serials

ConflictError: database conflict error (oid 0x08, class Products.Transience.Transience.Length2, serial this txn started with 0x0394fddba7126fbb 2012-03-08 07:23:39,157504, serial currently committed 0x0394fddbb0a4cb22 2012-03-08 07:23:41,400873)

Troubleshooting Suggestions

The URL may be incorrect.
The parameters passed to this resource may be incorrect.
A resource that this resource relies on may be encountering an error.

For more detailed information about the error, please refer to the error log.

If the error persists please contact the site maintainer. Thank you for your patience.

I tried to repaire the Data.fs without any errors...

Thanks in advance.

Answer 1

Conflict Errors occur when two users try to update the same object (often one that is part of a catalogue data structure) at the same time and the system cannot resolve the conflict. You should ensure that your ZEO server includes all of the eggs from the Zope instance to ensure you have all the conflict resolution code.

If you are seeing these on simple views, then it probably means you have some code that is updating the database on rendering that view. This is not a good idea with ZODB.