Oracle下session的查询与删除
Oracle下session的查询与删除 1、查询当前session SQLgt; select username,sid,serial# from v$session where username is not
Oracle下session的查询与删除
1、查询当前sessionSQL> select username,sid,serial# from v$session where username is not null;
USERNAME SID SERIAL#
------------------------------ ---------- ----------
SYS 144 4
HYL 146 48
SCOTT 147 64
HR 159 15
--SERIAL#:SID有可能会重复,,当两个session的SID重复时,SERIAL#用来区别session
SQL> alter system kill session '146,48';
System altered.
hyl的session下执行操作如下:
SQL> show user
USER is "HYL"
SQL> select * from test1;
select * from test1
*
ERROR at line 1:
ORA-00028: your session has been killed
--------------------------------------------------------------------------------
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3、删除当前session的用户思路:先关闭session,然后再删除用户
演示:在不关闭session的情况下删除用户现象:
SQL> select username,account_status from dba_users;
--查看当前有哪些用户
USERNAME ACCOUNT_STATUS
------------------------------ --------------------------------
CSMIG OPEN
MGMT_VIEW OPEN
SYS OPEN
SYSTEM OPEN
HYL OPEN
OE EXPIRED & LOCKED
6 rows selected.
SQL> select username,sid,serial# from v$session where username is not null;
--通过v$session视图,查看会话的sid、serial#
USERNAME SID SERIAL#
------------------------------ ---------- ----------
SYS 144 4
HYL 146 54
SCOTT 147 64
HR 159 15
SQL> drop user hyl; --删除,报错了,表明会话中存在的用户是不能被删除的,需要先将其关闭
drop user hyl
*
ERROR at line 1:
ORA-01940: cannot drop a user that is currently connected
SQL> alter system kill session '146,54';
System altered.
User dropped.
--尝试hyl连接,报错,无法使用hyl登陆session
SQL> conn hyl/oracle
ERROR:
ORA-01017: invalid username/password; logon denied
Warning: You are no longer connected to ORACLE.
--查看dba_users数据字典,表明hyl用户已经被删除
SQL> select username,account_status from dba_users;
USERNAME ACCOUNT_STATUS
------------------------------ --------------------------------
CSMIG OPEN
MGMT_VIEW OPEN
SYS OPEN
SYSTEM OPEN
OE EXPIRED & LOCKED
5 rows selected.
小结:
查询当前会话:select username,sid,serial# from v$session where username is not null;
删除当前会话:alter system kill session 'sid,serial#';
删除当前会话的用户,先kill session,再drop user(若用户下有对象,使用cascade命令)
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