php+mysqlprepare与普通查询的性能对比实例讲解

<?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);