如何根据MySQL的数据更新PHP页面上的Grid

I have MySQL table which is presently displayed using a grid-table on the PHP page. I want the data to be updated:

1. Where a particular field of a record displayed on PHP is changed.
2. Whenever a new record is added to the table.
3. Delete grid-table row when the record is deleted in the MySQL Table.

Step by step method to Update a field:

        //First the user will specify what field to Update  

        <form method="post">
            <p>Field to Update:
            <input type="text" name="pupdate"></p>

       //Next the user will update the field
            <p>Updated Name:
            <input type="text" name="pname"></p>
            <p><input type="submit" value="Add New"/></p>
        </form>

        <?php

         //To connect to database(If you dont understand the next line I can explain it further)
         require_once "db.php";

         if ( isset($_POST['pupdate']) && isset($_POST['pname']))
         {
             $up = $_POST['pupdate'];
             $u = $_POST['pname'];

        //This will update the database with the new field
        $sql = "UPDATE NAMEOFTABLE 
            SET pname='$u'
            WHERE pname='$up'";

        echo "<pre>
$sql
</pre>
";

        mysql_query($sql);
        }
        ?>