Thanks to all of you who spent time on that - that's what I finally did in my DBA application: http://www.usn-it.de/index.php/2009/06/16/string-concat-with-hierarchical-query-and-sys_connect_by_path-avoid-ora-30004/ Best regards Martin Klier -- Usn's IT Blog for Linux, Oracle, Asterisk http://www.usn-it.de -- //www.freelists.org/webpage/oracle-l