datatable editor - save changes in sql database

How do I save this to my sql database once it is edited?It lets me edit but then what?I am obviously new to this. Thank you for your help.

`<div   class="table-editor"   id="table_1"   data-mdb-entries="5"   data-mdb-entries-options="[5, 10, 15]"
>   <table class="table">
    <thead>
      <tr>
        <th class="th-sm">username</th>
        <th class="th-sm">fname</th>
                <th class="th-sm">lname</th>
                <th class="th-sm">email</th>
                <th class="th-sm">cellPhone</th>
      </tr>
    </thead>
    <tbody>

            <?php>          $db->query("SELECT * FROM users");             foreach ($db->results() as $record) {
                echo
                    "<tr>
                        <td>" . $record->username              . "</td>
                        <td>" . $record->fname                     . "</td>
                        <td>" . $record->lname                     . "</td>
                        <td>" . $record->email                     . "</td>
                        <td>" . $record->cellPhone             . "</td>
                    </tr>"
                ;           };          ?>

    </tbody>   </table> </div>`