DML TRIGGERS IN ORACLE DB

 -- Table for update trigger 

create table student_update_info (
id number primary key,
old_name varchar2(200),
new_name varchar2(200),
time_stamp varchar2(100),
message varchar2(200)
);

-- Table for insert and delete trigger 

create table student_info (
log_info varchar2(200), 
time_stamp varchar2(100)
)

-- AFTER INSERT Trigger

CREATE OR REPLACE TRIGGER student_insert_trigger
AFTER INSERT ON student
FOR EACH ROW
BEGIN
    -- Code to be executed after insert
    -- For example, logging the insertion along with timestamp
    INSERT INTO student_info (log_info , time_stamp) 
    VALUES ('New row inserted', TO_CHAR(SYSTIMESTAMP, 'DD-MON-YYYY HH:MI:SS AM'));
END;
/

-- After update trigger 

CREATE OR REPLACE TRIGGER student_update_trigger
AFTER UPDATE ON student
FOR EACH ROW
BEGIN
    IF :OLD.name <> :NEW.name THEN
        INSERT INTO student_update_info (id, old_name, new_name, update_date)
        VALUES (:OLD.id, :OLD.name, :NEW.name, TO_CHAR(SYSTIMESTAMP, 'DD-MON-YYYY HH:MI:SS AM'));
    END IF;
END;
/

-- AFTER DELETE Trigger

CREATE OR REPLACE TRIGGER after_delete_trigger
AFTER DELETE ON student
FOR EACH ROW
BEGIN
    -- Code to be executed after delete
    -- For example, logging the deletion
    INSERT INTO student_info (log_info, time_stamp) VALUES ('Row deleted', TO_CHAR(SYSTIMESTAMP, 'DD-MON-YYYY HH:MI:SS AM'));
END;
/