Hide and show button

mohon bantuan gan, bagaimana codingnya supaya button feedback hanya muncul kalau kolom feedback masih kosong dan klo kolom feedback sudah terisi maka button feedback akan hilang. Gambar: https://drive.google.com/open?id=1FF6FCrNQRtYL0SgPDbBL05kluRRYDnD0

<td>
<?php echo $data ['feedback']; ?>
</td>

<td width="100" align="center"><a class="btn btn-danger" href="javascript:cetakform(<?php echo $data ['cid']; ?>); ">Cetak</a> / <a class="btn btn-success" href="javascript:jelas(<?php echo $data ['cid']; ?>); ">Penjelasan</a> / <a class="btn btn-info" href="javascript:editclose(<?php echo $data ['cid']; ?>); ">Feedback </a> </td>
</tr>