BEFORE|AFTER|INSTEAD OF   INSERT ON TABLE

Will fire instructions before, after or instead of an INSERTon a table.

Syntax:
CREATE OR REPLACE TRIGGER MyTrigger
BEFORE INSERT ON Employee
DECLARE
–- list declare instructions
BEGIN
–Instructions
END MyTrigger;

BEFORE|AFTER|INSTEAD OF UPDATE ON TABLE

Will fire instructions before, after or instead of an UPDATE on a table.    

BEFORE|AFTER|INSTEAD OF DELETE ON TABLE

Will fire instructions before, after or instead of a DELETE on a table.

FOR EACH ROW

Add this on table trigger to make a Row Level Trigger

Syntax:
CREATE OR REPLACE TRIGGER MyTrigger
BEFORE INSERT ON Employee FOR EACH ROW
DECLARE
–- list declare instructions
BEGIN
–Instructions
END MyTrigger;

BEFORE|AFTER CREATE ON SCHEMA

Will fire instructions before or after executing a CREATE command on the schema.

Syntax:
CREATE OR REPLACE TRIGGER MyTrigger
BEFORE CREATE ON SCHEMA

DECLARE
–- list declare instructions
BEGIN–Instructions
END MyTrigger;

BEFORE|AFTER ALTER ON SCHEMA

Will fire instructions before or after executing an ALTER command on the schema.

BEFORE|AFTER DROP ON SCHEMA

Will fire instructions before or after executing a DROP command on the schema.

BEFORE|AFTER TRUNCATE ON SCHEMA

Will fire instructions before or after executing a TRUNCATE command on the schema.

BEFORE|AFTER CREATE ON DATABASE

Will fire instructions before or after executing a CREATE command on the database.

Syntax:
CREATE OR REPLACE TRIGGER MyTrigger
BEFORE CREATE ON DATABASE
DECLARE
–- list declare instructions
BEGIN
–Instructions
END MyTrigger;

BEFORE|AFTER DDL ON DATABASE

Will fire instructions before or after executing any DDL command on the database.

AFTER LOGON ON DATABASE

Will fire instructions after any login onto the system.

Syntax:
CREATE OR REPLACE TRIGGER MyTrigger
AFTER LOGON ON DATABASE CALL MyProcedure

AFTER STARTUP ON DATABASE

Will fire instructions after the system starts up.

BEFORE LOGOFF ON DATABASE

Will fire instructions before any logoff from the system.

BEFORE SHUTDOWN ON DATABASE

Will fire instructions before the shutdown of the system.

AFTER SERVERERROR ON DATABASE

Will fire instructions after any error occur on  the system.

Syntax:
CREATE OR REPLACE TRIGGER MyTrigger
AFTER SERVERERROR ON DATABASE

BEGIN
–Instructions
END MyTrigger;