php+mysql预查询prepare 与普普通通查询的性能对比_mysql

<?php   class timer {              public $StartTime = 0;              public $StopTime = 0;              public $TimeSpent = 0;                           function start(){                  $this->StartTime = microtime();              }                           function stop(){                  $this->StopTime = microtime();              }                           function spent() {                  if ($this->TimeSpent) {                  return $this->TimeSpent;                     } else {                    //  http://www.manongjc.com                 $StartMicro = substr($this->StartTime,0,10);                      $StartSecond = substr($this->StartTime,11,10);                      $StopMicro = substr($this->StopTime,0,10);                      $StopSecond = substr($this->StopTime,11,10);                      $start = floatval($StartMicro) + $StartSecond;                      $stop = floatval($StopMicro) + $StopSecond;                      $this->TimeSpent = $stop - $start;                                  return round($this->TimeSpent,8).'秒';                  }             }         }      $timer = new timer;      $timer->start();        $mysql = new mysqli('localhost','root','root','ganbaobao_ucenter');      /*  $query = $mysql->query("select username,email from uc_members where uid < 100000");  $result = array();  http://www.manongjc.com/article/1194.html while($result = $query->fetch_array())  {     $result[] = array('name'=>$result['username'],'email'=>$result['email']);  }  */   $query_prepare = $mysql->prepare("select username,email from uc_members where uid < ?");      $id = 100000;   $query_prepare->bind_param("i",$id);      $query_prepare->execute();   $query_prepare->bind_result($username,$email);      $result = array();   while($query_prepare->fetch())   {       $result[] = array('name'=>$username,'email'=>$email);   }      $timer->stop();     echo '</br>预查询mysql运行100000条数据时间为: '.$timer->spent();     unset($timer);     //var_dump($result);