trigger example

CREATE OR REPLACE TRIGGER trg_emp_insert
AFTER INSERT ON emp
FOR EACH ROW
BEGIN
— Insert into audit table
INSERT INTO emp (emp_id, emp_name,salary)
VALUES (:NEW.emp_name,:NEW.salary,:NEW.emp_id);

— Display message
DBMS_OUTPUT.PUT_LINE(‘Employee inserted successfully.’);

END;

insert into emp(emp_name,salary,emp_id)values(‘rohan’,3000,3);
select * from emp;

Example:

CREATE OR REPLACE TRIGGER trg_emp_insert
AFTER INSERT ON employees
FOR EACH ROW
BEGIN
    -- Insert into audit table
    INSERT INTO emp_audit (emp_id, emp_name, created_date)
    VALUES (:NEW.emp_id, :NEW.emp_name, SYSDATE);

    -- Display message
    DBMS_OUTPUT.PUT_LINE('Employee inserted successfully.');
END;
/

When you execute:

INSERT INTO employees (emp_id, emp_name)
VALUES (101, 'John');

The trigger:

1. Inserts a record into emp_audit.
2. Displays: Employee inserted successfully.

Important

• DBMS_OUTPUT.PUT_LINE only displays messages if SERVEROUTPUT is enabled in your SQL client: SET SERVEROUTPUT ON;
• In many applications (such as Oracle Forms, APEX, or Java/.NET applications), DBMS_OUTPUT is not shown to end users.

If you want to show an actual popup or stop the insert with an error message, use:

RAISE_APPLICATION_ERROR(-20001, 'Employee inserted successfully.');