php – ON DUPLICATE KEY UPDATE值;两次插入相同的值

我试图插入一些值,如果有一个DUPLICATE KEY updatE表人.我正在获取值的插入,但它重复值而不是进行更新.输入字段是动态的,可以添加或删除值.但我试图没有重复的价值观.如何插入新值,如果有重复键,然后更新字段？

Html /(不包括jquery函数生成更多输入字段)

<ul id="pq_entry_1" class="clonedSection">
        <li>
            <input id="person_fname_1" name="person_fname_1" placeholder="Person #1 - First Name" type="text" />
        </li>
        <li>
            <input id="person_lname_1" name="person_lname_1" placeholder="last name" type="text" />
        </li>
</ul>
<input type='button' id='btnAdd' value='add another Person' />
<input type='button' id='btnDel' value='delete delete' />

PHP / MySQL查询

//Insert or update Values 
        $f = 1;
        while(isset($_POST['person_fname_' . $f]))
        {

            $person_fname = $_POST['person_fname_' . $f];
            $person_lname = $_POST['person_lname_' . $f];


$query_init3 = "INSERT INTO person (academy_id,first_name,last_name) VALUES (:id,:person_fname,:person_lName) 
        ON DUPLICATE KEY updatE academy_id=:id,first_name=:person_fname,last_name=:person_lname";
        $query_prep3 = $db_con->prepare($query_init3);
            $query_prep3->execute(array(
                "id" => $id,"person_fname" => $person_fname,"person_lname" => $person_lname
            ));

            $f++;
        }

查询后的表：

@R_801_2763@ person ADD UNIQUE (person_fname,person_lName);