Back in the V6 days it was a desired characteristic to have every thing in the
first extent of an object for performance reasons. Thankfully those days are
gone and it really does not matter how many extents there are. Rachel has a
presentation on Oracle Myths where she actually portrays having
something along those lines...
as with everything there is no real black or white on this... but
transactional systems that do a lot of small (non-sequential) reads you
are better off with lots of extents while data warehouses are often
better off with fewer extents as the reads tend to be
I would content that the moment the extent size is
greater than SSTIOMAX (or whatever the OS can
service), then you won't see any benefit from fewer
extents even on data warehouse - the only exception I
can think is if you were lucky enough to be the only
user on a particular disk/volume during
