通过profile可以对用户会话进行一定的限制，比如IDLE时间。
将IDLE超过一定时间的会话断开，可以减少数据库端的会话数量，减少资源耗用。
使用这些资源限制特性，需要设置resource_limit为TRUE：
[oracle@test126 udump]$ sqlplus "/ as sysdba"
SQL*Plus: Release 10.2.0.1.0 - Production on Fri Oct 13 07:58:21 2006
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning and Data Mining options
SQL> show parameter resource
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
resource_limit boolean TRUE
resource_manager_plan string
该参数可以动态修改：
SQL> alter system set resource_limit=true;
System altered.
数据库缺省的PROFILE设置为：
SQL> SELECT * FROM DBA_PROFILES;
PROFILE RESOURCE_NAME RESOURCE LIMIT
-------------------- -------------------------------- -------- ---------------
DEFAULT COMPOSITE_LIMIT KERNEL UNLIMITED
DEFAULT SESSIONS_PER_USER KERNEL UNLIMITED
DEFAULT CPU_PER_SESSION KERNEL UNLIMITED
DEFAULT CPU_PER_CALL KERNEL UNLIMITED
DEFAULT LOGICAL_READS_PER_SESSION KERNEL UNLIMITED
DEFAULT LOGICAL_READS_PER_CALL KERNEL UNLIMITED
DEFAULT IDLE_TIME KERNEL UNLIMITED
DEFAULT CONNECT_TIME KERNEL UNLIMITED
DEFAULT PRIVATE_SGA KERNEL UNLIMITED
DEFAULT FAILED_LOGIN_ATTEMPTS PASSWORD 10
DEFAULT PASSWORD_LIFE_TIME PASSWORD UNLIMITED
PROFILE RESOURCE_NAME RESOURCE LIMIT
-------------------- -------------------------------- -------- ---------------
DEFAULT PASSWORD_REUSE_TIME PASSWORD UNLIMITED
DEFAULT PASSWORD_REUSE_MAX PASSWORD UNLIMITED
DEFAULT PASSWORD_VERIFY_FUNCTION PASSWORD NULL
DEFAULT PASSWORD_LOCK_TIME PASSWORD UNLIMITED
DEFAULT PASSWORD_GRACE_TIME PASSWORD UNLIMITED
16 rows selected.
创建一个允许3分钟IDLE时间的PROFILE：
SQL> CREATE PROFILE KILLIDLE LIMIT IDLE_TIME 3;
Profile created.