SQL>
SQL> CREATE OR REPLACE TRIGGER town_crier
2 AFTER CREATE ON SCHEMA
3 BEGIN
4 DBMS_OUTPUT.PUT_LINE('I believe you have created something!');
5 END;
6 /
Trigger created.
SQL>
SQL> SET SERVEROUTPUT ON
SQL> CREATE TABLE a_table
2 (col1 NUMBER);
I believe you have created something!
Table created.
SQL>
SQL> DROP TABLE a_table;
Table dropped.
SQL>