完全掌握php实现mysql连接池效果实现方法

 true);

    for ($i=0; $i < self::POOLSIZE; $i++) { 
      $connection = new PDO("mysql:dbname=$db;host=$host", $username, $password);
      // sleep(3);
      array_push($this->_pools, $connection);
    }
  }

  //从数据库连接池中获取一个数据库链接资源
  public function getConnection()
  {
    echo 'get' . count($this->_pools) . "
";
    if (count($this->_pools) > 0) {
      $one = array_pop($this->_pools);
      echo 'getAfter' . count($this->_pools) . "
";
      return $one;
    } else {
      throw new ErrorException ( "数据库连接池中已无链接资源，请稍后重试!" );
    }
  }

  //将用完的数据库链接资源放回到数据库连接池
  public function release($conn)
  {
    echo 'release' . count($this->_pools) . "
";
    if (count($this->_pools) >= self::POOLSIZE) {
      throw new ErrorException ( "数据库连接池已满!" );
    } else {
      array_push($this->_pools, $conn);
      // $conn = null;
      echo 'releaseAfter' . count($this->_pools) . "
";
    }
  }

  public function query($sql)
  {
    try {
      $conn = $this->getConnection();
      $res = $conn->query($sql);
      $this->release($conn);
      return $res;
    } catch (ErrorException $e) {
      print 'error:' . $e->getMessage();
      die;
    }
  }

  public function queryAll($sql)
  {
    try {
      $conn = $this->getConnection();
      $sth = $conn->prepare($sql);
      $sth->execute();
      $result = $sth->fetchAll();
      return $result;
    } catch (PDOException $e) {
      print 'error:' . $e->getMessage();
      die;
    }
  }
}

query($sql);
  // var_dump($res) . PHP_EOL;
}

class BaseMysql extends Model {
  protected $connection = array(
    'db_type' => 'mysql',
    'db_user' => '***',
    'db_pwd' => '*******',
    'db_host' => '*******',
    'db_port' => '3306',
    'db_name' => 'custom',
    'db_params' => array('persist' => true),
  );
}