php+mysql prepare 与普通查询的性能对比实例讲解

实例代码如下：

									<?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);