On 28/09/05, David Sharples wrote:
why would it want to do that?
On 9/28/05, Lou Fangxin wrote:
Maybe Oracle will add a default index tablespacce to user.
I seem to recall that an enhancement request was submitted for this
some time ago.
There seem to be different schools of thought on whether indexes
should be in the same tablespace as the tables, different tablespaces
but on the same disks/volumes or different tablespaces on different
I seem to recall reading something by Connor where he debunked the
myth that putting tables and indexes on separate disks improves
performance because Oracle can read the index and the table without
having to move the disk heads back and forth. It doesn't work that
way, Oracle doesn't read them in parralell it reads the index and then
the table. What I read did seem to only consider a single
My gut feeling is that, like many things in Oracle (and IT in
general), it depends on your app. There may be some apps that would
benefit from indexes being stored separately to tables, one possible
example that comes to mind is where you have a large number of
similtaneous queries by a key value that are widely dispersed accross
a large table (e.g. queries to an inventory table from an ordering
system where products are selected by a product ID which is the
primary key). Due to there being a large number queries all running
at the same time there's a good chance of the table and it's index
being read at the same time albeit by different processes.