php+mysql预查询prepare 与普通查询的性能对比

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']); 
} 
*/  
/* http://www.manongjc.com/article/1593.html */
$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);  

普通mysql运行1000条数据时间为: 0.011621秒

普通mysql运行10000条数据时间为: 0.07766891秒

普通mysql运行100000条数据时间为: 0.10834217秒

预查询mysql运行1000条数据时间为: 0.00963211秒

预查询mysql运行10000条数据时间为: 0.04614592秒

预查询mysql运行100000条数据时间为: 0.05989885秒