php Mysql use join

[yu-hsiang su]

This sql talk me DB error.

<?php
header("Content-Type:text/html; charset=utf-8");
$db_host = "XXXXXX" ;
$db_name = "XXXXX" ;
$db_user = "XXXXXXX";
$db_password = "XXXXXX" ;

$connection=mysql_pconnect($db_host , $db_user ,$db_password ) ;
mysql_select_db($db_name);
mysql_query("SET NAMES utf8",$connection);

$sqlstr = "SELECT `city.village`, `member.account` FROM `city` JOIN `member` ON `city.localnum` = `member.localnum`";


$result = mysql_query($sqlstr) or die("DB Error");
while ($row=mysql_fetch_array($result))
{
$str.= $row['city.village']."@".$row['member.account'].";";
}
echo $str=substr($str,0, strlen($str));
?>