仅使用php从sql数据库中的html表更新数据。 table td正在使用contenteditable属性

I want to make an archive from inputs that some user stored. Those inputs then output to html table. I want it now to make a option to edit a title of "Naslov poročila" for which i used contenteditable attribute. How can i read out the new value and update in database using only php ? i cant use anything other because teacher allows only php for it. Thank you. This is how it looks : Look of archive

This is what i used to generate that table:

while($fetch = mysqli_fetch_assoc($query)){

            echo "<tr>
            <td>".$fetch["vnosiID"].
            "<td contenteditable>".$fetch["naslov"]."</td>".
            "<td>".date('d.m.Y',strtotime($fetch["datum"]))."</td>".
            "<td>".date('d.m.Y',strtotime($fetch["datumDogodka"]))."</td>".
            "<td>".$fetch["ime"].'</td>'.
            "<td contenteditable = 'false' border=0 id='test'><button id='gumb' name='".$fetch["vnosiID"]."'>POSODOBI</a></td>".
            '</tr>';

        }

//name='".$fetch["vnosiID"]." <--- i used this to name every button by number of ID so i could easier check which field to update ...

sql database "naslov" must update ... if u need anything else please tell me, i tried few tutorials but none works out for me ..