MySQL sort after argument in IN()

Question

I have string containing a lot of IDs corresponding to my database. Like:

1,2,3,4,5

I then do a mySQL query to select all those rows:

Answer 1

you want the find_in_set function

$list = "1,2,....";
$sql = "select * from table where id in($list) order by find_in_set($id, '$list')";

another (probably faster) option is to do sorting in php:

$list = array(2, 3, ...);
$s    = implode(',', $list);
$sth  = mysql_query("select * from table where id in($s)");

$rows = array();
while($r = mysql_fetch_object($sth))
    $rows[$r->id] = $r;

$sorted_rows = array();
foreach($list as $id)
   $sorted_rows[] = $rows[$id];