Pro/cons to have indexes on its own tablspace

Question

hi ,
i have a new db running on oracle 10G R2 , various table spaces have been created that can be extended from 8M , 2M , 128K
my dba recommends that large insertion/updates tables goes to the 8M tablespace , but i notice that the indexes of those tables are in the same tablespace
ques :
1. can index exists on its own tablespace
2 . are there pro/cons of having indexes in its own tablspace ?
tks & rgds

Answer 1

Not really the proper forum for this question. You should have rather posted the question to the [url http://forums.oracle.com/forums/forum.jspa?forumID=61]Database Forum
> 1. can index exists on its own tablespace
Yes.
> 2 . are there pro/cons of having indexes in its own tablspace ?
Maybe.. it depends entirely on what your requirements are, and the nature of the data and hardware.
One reason to place indexes in a separate tablespace is simply for space management. E.g. this prevents some idiot developer of eating up all the space for tables, by indexing each and every column in a table and swamping the tablespaces with indexes.
Another reason is block sizes. Tablespaces can each have a different block sizes. You may want to use large 128KB blocks for data and smaller 32KB blocks for indexes.
That all said - personally I tend these days to prefer a single tablespace per logical database/application. In the past (especially back in Oracle 7) I always separated indexes and tables. But Oracle space management has improved so much, and we're dealing with such large data volumes these days, I do not think it is warranted without some sound technical reason to split data and indexes.