CREATE OR REPLACE TRIGGER YOUR_SCHEMA.REPLICATE_EMP 
  AFTER INSERT OR DELETE OR UPDATE 
  OF EMPNO, ENAME, SALARY ON YOUR_SCHEMA.EMP 
  REFERENCING NEW AS N OLD AS O FOR EACH ROW
BEGIN
  IF INSERTING THEN
    INSERT INTO OTHER_SCHEMA.COPY_EMP (EMPNO,ENAME,SALARY)
    VALUES (:N.EMPNO, :N.ENAME, :N.SALARY);
  ELSIF UPDATING THEN
    UPDATE OTHER_SCHEMA.COPY_EMP
    SET    EMPNO = :N.EMPNO,
           ENAME = :N.ENAME,
           SALARY = :N.SALARY
    WHERE  EMPNO = :O.EMPNO;
  ELSIF DELETING THEN
    DELETE FROM OTHER_SCHEMA.COPY_EMP
    WHERE EMPNO = :O.EMPNO;
  END IF;
END;
/