php连接数据库并显示表内容

<?php
 $con = mysql_connect("localhost","root","");
 if(!$con)
 {
  die("connect error");
 }else
  echo "connect success";
 mysql_select_db("test",$con);
 $sql = "select *from mytable";
 $result = mysql_query($sql);
 while($row = mysql_fetch_array($result))
 {
  echo $row['id'],$row['value'];
 }
 mysql_close($con);
?>