We've got a load process thats is taking a huge amount of time ( Solaris 8) and from looking at the code the statements used are just using insert append without disabling indexes etc. My thoughts on speeding this up are:
Turn logging off for tables invlolved
mark indexes unusable
alter session set skip_unusable_indexes=true
load data using insert append
rebuild indexes unrecoverable
turn logging back on for tables

any comments on this being a reasonable high level approach or not?