Oracle8i Application Developer's Guide - Fundamentals Release 8.1.5 A68003-01 |
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System events, like LOGON
and SHUTDOWN
, provide a mechanism for tracking system changes. With Oracle, this tracking can be combined with database event notification. Database event notification provides a simple and elegant method of delivering asynchrononous messaging to an application.
This chapter includes descriptions of the various events on which triggers can be created. It also provides the list of event attribute functions.
You can obtain certain event-specific attributes when a trigger is fired. These attributes can be used as standalone functions.
CATPROC
.SQL
script.
Table 14-1 System Defined Event Attributes
Resource manager events are related to instance startup and shutdown.Triggers created on resource manager events must be associated with the database object.
Table 14-2 contains a list of resource manager events.
Client events are the events related to user logon/logoff, DML, and DDL operations. For example:
CREATE OR REPLACE TRIGGER On_Logon AFTER LOGON ON The_user.Schema BEGIN Do_Something; END;
Table 14-3 contains a list of client events.