Applies to:

Oracle Server Enterprise Edition - Version: 8.0.3.0 to 11.2.0.1.0
Information in this document applies to any platform.
Oracle Server - Enterprise Edition - Version: 8.0 to 11.2

Goal

Oracle Internal Events, both named event (eg: ERRORSTACK) as numeric events (eg 10046) can be set at the session level. This document outlines how DataBase Administrators can verify which events have been set in a specific session or in the entire system.

Solution

This can be achieved through the ORADEBUG functionality. The exact syntax to use depends on the Oracle version you are using.

If you want to retrieve the events set in a specific session, then use the following oradebug commands to identify the session:

1. identify the session 

   SQL> select p.pid, p.spid, s.username 
        from v$process p, v$session s 
        where p.addr = s.paddr; 


2. Attach to the desired session 

   SQL> connect / as sysdba   
   SQL> oradebug setorapid 
   --OR-- 
   SQL> oradebug setospid 
   ...

If you want to retrieve the events set in your current SESSION or at the SYSTEM level, you can use the following commands:

SQL> connect / as sysdba
SQL> oradebug setmypid
...

 

Oracle 8i / 9i / 10g

SQL> oradebug dump events 

Level 1 - Dump session group's event settings 
Level 2 - Dump process group's event settings 
Level 4 - Dump system group's event settings (Ie the instance wide events) 

 

Oracle 10g / 11g and above

SQL> oradebug eventdump 

SESSION - Dump session group's event settings 
PROCESS - Dump process group's event settings 
SYSTEM  - Dump system group's event settings (Ie the instance wide events)

             -- OR --

SQL> alter session set events 'immediate eventdump()';

SESSION - Dump session group's event settings
PROCESS - Dump process group's event settings  
SYSTEM  - Dump system group's event settings (Ie the instance wide events)

 

Example 1:  Oracle 9i - system events

This example illustrates how to retrieve the events set at the system level in an Oracle 9i database.

After the event is set we dump the events information

The following information will be dumped in the in the trace file ORCL_ora_2620.trc.

Notice the line 2 "Dump event group for level SYSTEM" which tells you which level was used to dump the information. In our case level 1 was used to dump the session information.

In line 4 the second column value tells us the event that was set, in our case 942.

In line 6 the first column tells us the name of the event, in our case the named event "ERRORSTACK" appears. On the same line check the second column, the determines the level at which the event was set, in our case "3"

Hence from the above information was can conclude that the event "942 trace name ERRORSTACK level 3" was set at the system level

 

Example 2: Oracle 11g - events set at session user SCOTT

This example illustrates how to retrieve the events user SCOTT has set at his session in an Oracle 11g database: 

Attach to the above identified session:

Get the event information:

 

Example 3: Oracle 11g - events set at your current session

This example illustrates how to retrieve the events set in your current session environment in an Oracle 11g database:

The following information will be dumped in the in the trace file l112_ora_32493.trc

 

Comparison with DBMS_SYSTEM.READ_EV

We can also use the prodecure READ_EV from the package DBMS_SYSTEM to get the events set in the database. But the main difference between the usage would be that the DBMS_SYSTEM.READ_EV will generate information only on the numeric events like 10235, 10046, etc., that are set in the database. But, checking the events with the help of this named event "EVENTS", we can check for both the named and numerical events that are set. Also we can get additional information regarding each event that is set, from the trace file generated. 

For example, ERRORSTACK, HEAPDUMP in following format cannot be checked through DBMS_SYSTEM.READ_EV,

  ALTER SYSTEM SET EVENTS '4031 TRACE NAME HEAPDUMP LEVEL 2';

  ALTER SYSTEM SET EVENTS '942 TRACE NAME ERRORSTACK LEVEL 3';

but can be checked through the named event 'EVENTS'.