PHP连接SQL SERVER突然不行了：（

这样写试试:
<?
$mssql_hostname = "ALEX\ALEX";
$mssql_hostuser = "sa";
$mssql_hostpasswd = "alex";
$mssql_hostdb = "sim";
$link=mssql_connect($mssql_hostname,$mssql_hostuser,$mssql_hostpasswd) or die("error_connect");
mssql_select_db($mssql_hostdb,$link);//注意这里$res=mssql_query("select count(*) as aa from user");
$data=mssql_fetch_array($res);
echo $data["aa"];
?>