Memcache doesn't set keys
I am having a problem with Memcache being unable to set a key. Basically I have my testing page:

    $db=new db;
    $my_test_cache=$db->query("SELECT `txt` FROM `lang` WHERE `pg`='front' LIMIT 2", 10);

And a db class for caching:

    class db {
    		public function query($query, $ttl=30, $cache=true, $compr=false) {
    			global $memcache;
    			if ($cache=true) {
    				$res=$memcache->get(hash('md4', $query));
    				if ($res!=false) {
    					echo 'this is cached';
    					return $res;
    				}
    				else {
    					$res=mysql_query($query);
    					$memcache->set(hash('md4', $query), $res, $compr, $ttl);
    					echo 'this is not cached<hr>
    					Query: ',$query,'<br/>
    					Md4: ',hash('md4',$query),'<br/>';
    					var_dump($res);
    					return $res;
    				}
    			}
    			else return mysql_query($query);
    			unset($res, $query);
    		}
    	}

Sadly, this does not set any data to cache, even though all the resources seem to work properly. AKA my page outputs:

 - this is not cached Query: SELECT * FROM `lang` WHERE `pg`='front'
   LIMIT 2
 - Md4: 34aa4e46a15413f5091dac79c9e86306
 - resource(7) of type (mysql result)

Would anyone be so kind as to tip me off on what to do here?
Memcache doesn't set keys
===

I am having a problem with Memcache being unable to set a key. Basically I have my testing page:

    $db=new db;
    $my_test_cache=$db->query("SELECT `txt` FROM `lang` WHERE `pg`='front' LIMIT 2", 10);

And a db class for caching:

    class db {
    		public function query($query, $ttl=30, $cache=true, $compr=false) {
    			global $memcache;
    			if ($cache=true) {
    				$res=$memcache->get(hash('md4', $query));
    				if ($res!=false) {
    					echo 'this is cached';
    					return $res;
    				}
    				else {
    					$res=mysql_query($query);
    					$memcache->set(hash('md4', $query), $res, $compr, $ttl);
    					echo 'this is not cached<hr>
    					Query: ',$query,'<br/>
    					Md4: ',hash('md4',$query),'<br/>';
    					var_dump($res);
    					return $res;
    				}
    			}
    			else return mysql_query($query);
    			unset($res, $query);
    		}
    	}

Sadly, this does not set any data to cache, even though all the resources seem to work properly. AKA my page outputs:

 - this is not cached Query: SELECT * FROM `lang` WHERE `pg`='front'
   LIMIT 2
 - Md4: 34aa4e46a15413f5091dac79c9e86306
 - resource(7) of type (mysql result)

Would anyone be so kind as to tip me off on what to do here?