DECLARE
    -- declaration of variable
BEGIN
    -- PL/SQL
EXCEPTION
    -- custom exception
    WHEN e_custom_exception THEN
        DBMS_OUTPUT.PUT_LINE('Caught an exception: Custom exception raised');
    -- divide by zero
    WHEN ZERO_DIVIDE THEN
        DBMS_OUTPUT.PUT_LINE('Caught an exception: Division by zero');
    -- invalid number
    WHEN INVALID_NUMBER THEN
        DBMS_OUTPUT.PUT_LINE('Caught an exception: Invalid number');
    -- other exceptions
    WHEN OTHERS THEN
        DBMS_OUTPUT.PUT_LINE('Caught an exception: ' || SQLERRM);
END;