$result=$this->db->query($sql,$values);
 
makes use of "prepare" internally and doesn't free the results.
 
e.g., the following script, does one query 5 times and annother time with different values, yet when done, diagnose() prints out that 6 lots of prepare_tokens, prepare_types, prepare_queries were stored in the db object!

I reckon at least they should have been destroyed when the results were destroyed (if no results, then right away!).

<?php

include_once("DB.php");

$_db=array(
    'phptype'  => "pgsql",
    'hostspec' => "localhost",
    'database' => "*****",
    'username' => "*******",
    'protocol' => "unix",
    'password' => "***********");

$db=DB::connect($_db);
if (DB::isError($db)) {
  die("Can't connect");
}

$sql="select ?";
QUERY($db,$sql,array(1));
QUERY($db,$sql,array(1));
QUERY($db,$sql,array(1));
QUERY($db,$sql,array(1));
QUERY($db,$sql,array(1));
QUERY($db,$sql,array(2));

var_dump($db);
diagnose($db);

function diagnose(&$db) {
  foreach($db as $key=>$val) if (eregi('^prepare',$key) && is_array($val)) {
    print count($val). " of $key\n";
  }
}

function QUERY(&$db,$sql,$array) {
  $result=$db->query($sql,array(1));
  if (DB::isError($result)) {
    die ("Dead: ".$result->userinfo);
  }
  $numRows=$result->numRows();
  if ($numRows>1) die ("Too many matches for $query,");
  if ($numRows) {
    $data=$result->fetchRow(DB_FETCHMODE_ASSOC);
  }
  if (is_object($result)) $result->free();
  return $data;
}
?>