And just in case there is any ambiguity, it does not matter whether the sort operation is based on a normal permanent table or a global temporary table. Either way this test produces the same result, indicating that there is no redo during a sort-to-disk operation. regards _________________________ David Kurtz Go-Faster Consultancy Ltd. tel: +44 (0)7771 760660 fax: +44 (0)7092 348865 web: www.go-faster.co.uk mailto:david.kurtz@xxxxxxxxxxxxxxx Book: PeopleSoft for the Oracle DBA: http://www.psftdba.com PeopleSoft DBA Forum: http://groups.yahoo.com/group/psftdba > -----Original Message----- > You are right, as usual. I created a bit larger table and forced > sort to disk. Redo size remained the same: > > NAME > VALUE > ---------------------------------------------------------------- > ---------- > sorts (memory) > 2741 > sorts (disk) > 2 > sorts (rows) > 4017884 > > SQL> select n.name,s.value > from v$statname n, v$mystat s > where n.statistic#=s.statistic# and > name = 'redo size'; 2 3 4 > > NAME > VALUE > ---------------------------------------------------------------- > ---------- > redo size > 672 > > SQL> select count(*) from scott.test_redo; > > COUNT(*) > ---------- > 2000001 > > Redo size was 672 before sorts that were forced by setting > WORKAREA_SIZE_POLICY to > "MANUAL" and setting the sort_area_size for the session to 64K. > The LED on my > hard disk immediately showed intense disk activity, but redo size > remained the same. > Had there been redo activity, it would have shown. GTT are > obviously a very special > case. > > -- > Mladen Gogala > http://www.mgogala.com -- //www.freelists.org/webpage/oracle-l