SQL>
SQL> CREATE OR REPLACE TRIGGER no_create
2 AFTER DDL ON SCHEMA
3 BEGIN
4 IF ORA_SYSEVENT = 'CREATE' THEN
5 RAISE_APPLICATION_ERROR(-20000,'Cannot create the ' || ORA_DICT_OBJ_TYPE ||
6 ' named ' || ORA_DICT_OBJ_NAME ||
7 ' as requested by ' || ORA_DICT_OBJ_OWNER);
8 END IF;
9 END;
10 /
Trigger created.
SQL>
SQL> drop trigger no_create;
Trigger dropped.