Subject:  Oracle8i Dynamic System Wide Events 
Creation Date:  13-OCT-1998 

Event : All
Versions : 8.1.4 + 


DYNAMIC SYSTEM WIDE EVENTS
==========================

From Version 8.1.4 and upward, DBA's Support Analysts etc. can set diagnostic
events for the entire instance, without shutting and restarting the instance.
This happens immediately, though existing sessions are unaffected. 

e.g. 

ALTER SYSTEM SET EVENTS '10046 TRACE NAME CONTEXT FOREVER, LEVEL 12';

Currently turns on tracing for all NEW sessions. Existing sessions and
background processes are unaltered. Use  oradebug to signal events to 
existing processes and backgrounds. System wide events can also be turned
off in the usual manner.

e.g. 

ALTER SYSTEM  SET EVENTS '10046 TRACE NAME CONTEXT OFF';

This will be of most use where we are trying to trap a specific error, 
but do not know which process is going to hit it, but equally we cannot
bounce the database to set the event in the init.ora.