Pawel, Outside of the oracle bugs (I assume you are researching the suitability/ applicability in your environment), have you looked into the any effect of CTAS statements. (By any chance, are these CTAS statements running in parallel ?) Check if the CTAS running with parallel sessions is gobbling up your temp tablespace and making database processing come to a frozen/hang state. -Rajeev -- //www.freelists.org/webpage/oracle-l