PHP程序员笔试：请写一段PHP MYSQL基本操作的代码

<?php $dbhost=’localhost’;

$dbuser=’root’; $dbpass=’123456′;

$dbname=’products’;

$connect=mysql_connect($dbhost,$dbuser,$dbpass);

if(!$connect) exit(‘数据库连接失败！’);

mysql_select_db($dbname,$connect);

mysql_query(‘set names utf8’); //查询

$sql=”SELECT * FROM `category`”;

$result=mysql_query($sql); while($row=mysql_fetch_array($result)){ echo $row[‘id’]; }

//插入

$sql=”INSERT INTO `category` (`id`,`name`) VALUES (NULL,'”.$name.”‘)”; $result=mysql_query($sql); if(mysql_affected_rows()){ echo ‘插入成功，插入ID为：’,mysql_insert_id(); }else{ echo ‘插入失败：’,mysql_error(); } //修改 $sql=”UPDATE `category` SET `name`='”.$name.”‘ WHERE `id`='”.$id.”‘”; $result=mysql_query($sql); if(mysql_affected_rows()){ echo ‘修改成功！’; }

//删除 $sql=”DELETE FROM `category` WHERE `id`='”.$id.”‘”; $result=mysql_query($sql); if(mysql_affected_rows()){ echo ‘删除成功！’; }

//关闭连接

mysql_close($connect);