Only the first IF statement out of 3 is executed within a PHP loop

The following code uploads multiple images no problem. However, I'm trying to get it to update a field in a table based on what iteration the loop is in. PROBLEM: The IF Statement seems to not work when looped. I.e. it only adds the first file_name to the database.

Anyone see what I'm doing wrong here? Much appreciated if so!!!

for ($i = 1; $i < 4; $i++)
{开发者_运维百科
  /* Handle the file upload */
  $upload = $this->upload->do_upload('image' . $i);

  /* File failed to upload - continue */
  if ($upload === FALSE)
    continue;

  /* Get the data about the file */
  $data = $this->upload->data();

  $uploadedFiles[$i] = $data;

  if ($i == 1)
  {
    $filenames1 = array(
      'product_image_front' => $data['file_name'],
    );

    $this->db->where('id', $this->db->insert_id());
    $this->db->update('products', $filenames1);
  }

  if ($i == 2)
  {

    $filenames2 = array(
      'product_image_back' => $data['file_name'],
    );

    $this->db->where('id', $this->db->insert_id());
    $this->db->update('products', $filenames2);
  }

  if ($i == 3)
  {

    $filenames3 = array(
      'product_image_back' => $data['file_name'],
    );

    $this->db->where('id', $this->db->insert_id());
    $this->db->update('products', $filenames3);
  }

}

insert_id - Get the ID generated in the last query.

Store it in a variable before the loop.