This message appeared when one data field at the endpoint was empty. Data from other fields appeared fine so this message would be disconcerting to the average user. Also, the message seems to be geared for a site admin. Perhaps the message could be relegated to an admin view and a more helpful phrasing for the user display might be "No data available" and perhaps it would be more helpful to have it appear in the area the data was supposed to be - in my case, at the top of a block - rather than at the top of the page.

Notice: Undefined property: stdClass::$dbpedia_description_field_thumbnail in sparql_views_handler_field->image() (line 251 of .../sites/all/modules/sparql_views/handlers/sparql_views_handler_field.inc).

7.x-2.0-beta1+11-dev