Mysql order by photo_id desc and shuffle after

You could put them all in an array in PHP, then randomize the order of that array with shuffle(), or make the query to select the most recent 12 a sub query, then randomize the results with the outer query. using mysql_fetch_assoc() rather than _array() should help things remain clear after shuffling.

You could use a subquery:

SELECT * FROM (
  SELECT `migo_artig_photos`.`photo_id`,
         `migo_artig_photos`.`photo_name`
  FROM   `migo_artig_photos`
  WHERE  `migo_artig_photos`.`photo_deleted` = 0 AND
         `migo_artig_photos`.`photo_type` = 2
  ORDER BY photo_id DESC
  LIMIT 12) `top_12_migo_artig_photos`
ORDER BY RAND();

PHP's shuffle() function removes any existing keys from your array:

Note: This function assigns new keys to the elements in array. It will remove any existing keys that may have been assigned, rather than just reordering the keys.

This function is best used with numerically indexed arrays. A quick approach would be to just write your own shuffle function that works on associative arrays. I found this one on a previous Stack Overflow post:

function shuffle_assoc($list) { 
  if (!is_array($list)) return $list; 

  $keys = array_keys($list); 
  shuffle($keys); 
  $random = array(); 
  foreach ($keys as $key) { 
    $random[] = $list[$key]; 
  }
  return $random; 
} 

Link to the original:

PHP Random Shuffle Array Maintaining Key => Value