FieldIndex: unindex_object could not remove documentId

We are seeming random errors in Plone 3.3 logs:

78: ERROR Zope.UnIndex FieldIndex开发者_运维技巧: unindex_object could not remove documentId 513478895 from index getCompleteness. This should not happen.

getCompleteness is our custom index coming from an Archetypes accessor method.

What does this error mean?

Should there be action taken e.g. by adding some special to custom add-ons?

It means that your portal_catalog - in particular one or more indexes - are inconsistent. There are various reasons why the portal_catalog can be become inconsistent. Either through issues in the index implementation or through errors in the application code. In such a case you should try "Clear and Rebuild" from the ZMI.

It means that your catalog was inconsistent; it thought it had indexing information for one document, and on un-index it couldn't find that same information anymore.

After this error, your catalog is actually a little less inconsistent as the document is no longer inconsistently indexed. The catalog is quite resilient in that way.

If you see the error more often, you'll need to verify that your custom index is taking care of indexing and unindexing properly, as it's internal data structures are getting out of sync more often.