Oracle 触发器，个人对触发器不如何熟悉，希望能写明白点，多谢

Oracle 触发器，个人对触发器不怎么熟悉，希望能写明白点，谢谢
                              create table  emp_info
                                    (
                                      id int primary key ,
                                      name varchar(20),
                                      address varchar(50)
                                      creation_date date,
                                      creator  varchar(50)
 );

                                    create table emp_info_bk
                                    (
                                    operation_type  varchar(50),
                                    oprtation_date  date,
                                    id  int  primary key,
                                    name varchar(20),
                                    address varchar(50)
                                     ) 
这是两张表
寫一個觸發器，操作一個表（emp_info）時，向另一個表（emp_info_bk）插入操作的內容。測試向其中插入 " ' "  , " | " 字符？

       
------解决方案--------------------

引用:

                              create table  emp_info
                                    (
                                      id int primary key ,
                                      name varchar(20),
                                      address varchar(50)
                                      creation_date date,
                                      creator  varchar(50)
 );

                                    create table emp_info_bk