如何查詢會話 event

很多時候，我們在數據庫中設置了event,如何確認設置的event生效或者如何確認你的庫中設置了什麼event.下面的文章測試了在11g中比較方便的方法
數據庫版本

SQL>
select

* from

v$version;

BANNER

--------------------------------------------------------------------------------

Oracle
Database

11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production

PL/SQL
Release 11.2.0.3.0 - Production

CORE   
11.2.0.3.0      Production

TNS
for

Solaris: Version 11.2.0.3.0 - Production

NLSRTL
Version 11.2.0.3.0 - Production

設置測試event

SQL>
alter

session set

events '10510
trace name context forever,level 1';

Session
altered.

SQL>
alter

session set

events

  2 
'10046
trace name context forever,level 4';

Session
altered.

SQL>
alter

system set

events '60025
trace name context forever';

System
altered.

SQL>
alter

system set

events '10513
trace name context forever,level 2';

System
altered.

測試spfile參數中是否有event

SQL>
create

pfile='/tmp/pfile'

from 
spfile;

File
created.

solaris*orcl-/home/oracle$
grep -i event /tmp/pfile

--無記錄

SQL>
show parameter event;

NAME                                

TYPE        VALUE

------------------------------------
----------- -----------------

event                               
string

xml_db_events                       
string      enable

證明設置event不會在spfile中記錄

查詢會話event

--dbms_system實現

SQL>
set

serveroutput on

size 
1000000

SQL>
declare

  2 
event_level number;

  3 
begin

  4 
for

i in

1..100000 loop

  5 
sys.dbms_system.read_ev(i,event_level);

  6 
if (event_level > 0) then

  7 
dbms_output.put_line('Event
'||to_char(i)||'
set at level '||

  8 
to_char(event_level));

  9 
end

if;

 10 
end

loop;

 11 
end;

 12 
/

Event
10510 set

at 
level 
1

Event
10513 set

at 
level 
2

Event
60025 set

at 
level 
1

PL/SQL
procedure

successfully completed.

--oradebug實現

SQL>
oradebug SETMYPID

Statement
processed.

SQL>
oradebug eventdump session

10510
trace name

context forever,level

1

10513
trace name

context forever,level

2

60025
trace name

context forever

sql_trace
level=4

測試證明使用dbms_system可以捕獲到event,oradebug可以捕獲到本身會話,還可以通過setospid/setorapid來跟蹤其他會話的event設置情況.event 10046對應的本質是sql_trace所以使用dbms_system不能捕獲到10046

原文地址：http://www.xifenfei.com/2012/10/%E5%A6%82%E4%BD%95%E6%9F%A5%E8%AF%A2%E4%BC%9A%E8%AF%9D-event.html