Error (1791): ORA-01791: cette expression n'a pas été SELECTionnée
Failed query at offset 1217:
SELECT DISTINCT  substr( ezkeyword.keyword, 1, 10 )  AS keyword ,ezcontentobject_tree.node_id
                  FROM ezkeyword, ezkeyword_attribute_link,ezcontentobject_tree,ezcontentobject,ezcontentclass
                       , ezcontentobject_attribute a1
                       
                  WHERE
                   a1.version=ezcontentobject.current_version
                                             AND a1.contentobject_id=ezcontentobject.id AND
                  ezkeyword.keyword LIKE 'conference%'
                  AND ezcontentobject_tree.is_invisible = 0
                  
                  AND ezkeyword.class_id IN ( 0 ) 
                  
                  AND ezcontentobject_tree.parent_node_id = '0'
                  AND ezcontentclass.version=0
                  AND ezcontentobject.status=1
                  AND ezcontentobject_tree.main_node_id=ezcontentobject_tree.node_id
                  AND ezcontentobject_tree.contentobject_id = ezcontentobject.id
                  AND ezcontentclass.id = ezcontentobject.contentclass_id
                  AND a1.id=ezkeyword_attribute_link.objectattribute_id
                  AND ezkeyword_attribute_link.keyword_id = ezkeyword.id ORDER BY ezcontentobject.published DESC

Start of error:
ezcontentobject.published DESC