Greetings all, Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production, Windows 2008 R2 Enterprise. There is a select query which fails intermittently with ORA 600 [kdsgrp1] and generates huge .trc ORA-00600: internal error code, arguments: [kdsgrp1], [], [], [], [], [], [], [], [], [], [], [] ========= Dump for incident 795670 (ORA 600 [kdsgrp1]) ======== *** 2013-01-09 13:16:35.324 dbkedDefDump(): Starting incident default dumps (flags=0x2, level=3, mask=0x0) ----- Current SQL Statement for this session (sql_id=7nkvuwm6q9rtd) ----- V$active_session_history shows the select query has waited mostly on "log file sequential read" event. analyzing the table/index with validate structure doesn't help. I have not tried _row_crúLSE yet. Any pointers/help will be much appreciated. Thanks & Regards, Arvind Kumar -- //www.freelists.org/webpage/oracle-l