Database PHP 数据库抽象层使用静态类与单例对象

我不想创造一个关于单身比静电更好，或者比全球更好的讨论，等等.我在SO上读了几十个关于类似主题的问题，但是我想不出这个具体问题的答案，所以我希望现在有人能用一个(或更多)real simple EXAMPLES个回答这个问题来启发我，而不仅仅是理论上的讨论.

在我的应用程序中，我有typical DB class to abstract the DB layer，可以在数据库上执行任务，而不必到处用代码mysql_connect / mysql_select_db / mysql...编写

I could write the class either as a STATIC CLASS:个

class DB
{
   private static $connection = FALSE; //connection to be opened

   //DB connection values
   private static $server = NULL; private static $usr = NULL; private static $psw = NULL; private static $name = NULL;

   public static function init($db_server, $db_usr, $db_psw, $db_name)
   {
      //simply stores connections values, without opening connection
   }

   public static function query($query_string)
   {
      //performs query over alerady opened connection, if not open, it opens connection 1st
   }

   ...
}

OR as a SINGLETON:个

class DBSingleton
{
   private $inst = NULL;
   private $connection = FALSE; //connection to be opened

   //DB connection values
   private $server = NULL; private $usr = NULL; private $psw = NULL; private $name = NULL;

   public static function getInstance($db_server, $db_usr, $db_psw, $db_name)
   {
      //simply stores connections values, without opening connection

      if($inst === NULL)
         $this->inst = new DBSingleton();
      return $this->inst;
   }
   private __construct()...

   public function query($query_string)
   {
      //performs query over already opened connection, if connection is not open, it opens connection 1st
   }

   ...
}

然后在我的应用程序中，如果我想查询数据库，我可以这样做

//Performing query using static DB object
DB:init(HOST, USR, PSW, DB_NAME);
DB::query("SELECT...");

//Performing query using DB singleton
$temp = DBSingleton::getInstance(HOST, USR, PSW, DB_NAME);
$temp->query("SELECT...");

对我来说，Singleton唯一的优势是避免将类的每个方法声明为static.我相信你们中的一些人可以给我一个EXAMPLE分的单人版在这specific case分中的真正优势.提前谢谢您.