[color=blue]create or replace trigger AI_TEST_TR
after insert on TEST
for each row
begin
 DBMS_ALERT.signal('ALERT_TEST', 'TestMessage');
end AI_TEST_TR;[/color]

[color=red]Error: PLS- 00201 : identifier 'DBMS_ALERT' must be declared
Line:  7 
Text: DBMS_ALERT.signal('ALERT_TEST', 'TestMessage');[/color]