[ZODB-Dev] ConflictError: database conflict error

[Jim Fulton]

Bob Horvath wrote:
> What does the following mean?
> 
> 
> <TABLE BORDER="0" WIDTH="100%">
> <TR VALIGN="TOP">
> 
> <TD WIDTH="10%" ALIGN="CENTER">
> &nbsp;
> </TD>
> 
> <TD WIDTH="90%">
>  <H2>Site Error</H2>
>  <P>An error was encountered while publishing this resource.
>  </P>
>  <P><STRONG>ZODB.POSException.ConflictError</STRONG></P>
> 
>  Sorry, a site error occurred.<p><p>Traceback (innermost last):
> <ul>
> 
> <li>  Module ZPublisher.Publish, line 150, in publish_module</li>
> 
> <li>  Module ZPublisher.Publish, line 127, in publish</li>
> 
> <li>  Module ZPublisher.Publish, line 127, in publish</li>
> 
> <li>  Module ZPublisher.Publish, line 127, in publish</li>
> 
> <li>  Module ZPublisher.Publish, line 122, in publish</li>
> 
> <li>  Module Zope.App.startup, line 159, in zpublisher_exception_hook</li>
> 
> <li>  Module ZPublisher.Publish, line 102, in publish</li>
> 
> <li>  Module Zope.App.startup, line 217, in commit</li>
> 
> <li>  Module ZODB.Transaction, line 235, in commit</li>
> 
> <li>  Module ZODB.Transaction, line 350, in _commit_objects</li>
> 
> <li>  Module ZODB.Connection, line 410, in commit<br />
> __traceback_info__: (('BTrees._IOBTree', 'IOBucket'), 
> '\x00\x00\x00\x00\x00\x00\xcd#', '')</li>
> 
> <li>  Module ZODB.FileStorage, line 728, in store</li>
> 
> </ul>ConflictError: database conflict error (oid 000000000000cd23, 
> serial was 03597732139eabdd, now 0000000000000000)
> </p>
>  <HR NOSHADE>
> 
>  <P>Troubleshooting Suggestions</P>
> 
>  <UL>
>  <LI>The URL may be incorrect.</LI>
>  <LI>The parameters passed to this resource may be incorrect.</LI>
>  <LI>A resource that this resource relies on may be
>      encountering an error.</LI>
>  </UL>
> 
>  <P>For more detailed information about the error, please
>  refer to the error log.
>  </P>
> 
>  <P>If the error persists please contact the site maintainer.
>  Thank you for your patience.
>  </P>
> </TD></TR>
> </TABLE>

Assuming, as Tim suggsts that the serials are swapped, then this
suggests that two threads are trying to add objects with the same
object id, which shuldn't happen.

Does this problem persist? Is it reproduceable? Do you get it on every change?

As Tim suggested, more details would be helpful.

Jim

-- 
Jim Fulton           mailto:jim at zope.com       Python Powered!
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