you shuold really check before posting the stuff you do

SQL> show parameter session_cached_cursors

NAME TYPE VALUE
------------------------------------ -----------
session_cached_cursors integer 0

SQL> alter system set session_cached_cursors = 200;
alter system set session_cached_cursors = 200
*
ERROR at line 1:
ORA-02096: specified initialization parameter is not modifiable with this
option


you cant change the running instance, only in the spfile and reboot

Try reading the docs

http://download-uk.oracle.com/docs/c...tparams004.htm