Using temporary tablespaces to improve sort

Question

I have to do a select like "SELECT X FROM ABC ORDER BY X", where X is the primary key, thus, is indexed.
There is more than 80000 records, and its taking more than 10 seconds to get the response....
After creating a temporary tablespace, how do I do a Select using this tablespace?
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Answer 1

Hi everybody
Executing the script utlxplan.sql, and after the script explain.sql, I got the "route" done by the query I need.
The table's name is CADIT. Primary Key cod_cp. The column used for the where clause is familia,indexed with the index IT1.
In the first case, the query was
SELECT COD_CP FROM CADIT
WHERE FAMILIA='600' ORDER BY COD_CP
The plan is this:
OPERATION OPTIONS OBJECT_NAME
SELECT STATEMENT
SORT ORDER BY
TABLE ACCESS BY INDEX ROWID CADIT
INDEX RANGE SCAN IT1
In the second case, the query was SELECT COD_CP FROM CADIT WHERE FAMILIA='600'
The plan is this:
OPERATION OPTIONS OBJECT_NAME
SELECT STATEMENT
TABLE ACCESS BY INDEX ROWID CADIT
INDEX RANGE SCAN IT1
In the third case, the query was SELECT COD_CP FROM CADIT ORDER BY COD_CP
The plan is this:
OPERATION OPTIONS OBJECT_NAME
SELECT STATEMENT
SORT ORDER BY
TABLE ACCESS FULL CADIT
Thus, looking at it, I concluded that no index is used for the SORT operation. Is that correct?
I created another table, named cadit2, with the parameter ORGANIZATION INDEX at the end of the CREATE TABLE command. For that new table, the same query as the first one was much faster. Why?
Thanks
Guillermo Nudelman Hess