有关php连接sql server的问题

[wenan]

$server=mssql_connect("10.74.13.10:1433","web","web");
if($server) echo "true"; else echo "false";
echo "<br>";
$db=mssql_select_db("SMSC_CENTER",$server);
if($db) echo "dbtrue"; else echo "false";
$str_Sql="select sm_count from SMFee where teln='$t_tele_num' ";
$result=mssql_query($str_Sql,$db);
$sms_count=mssql_fetch_field($result);

上面这段是我写的代码，但是提示4，7，8行出错
Warning: 0 is not a Sybase link index
连接的不是本机的sql server数据库，请大家帮我下，哪里有问题？该怎么改？

[wd_318]

<?php
$servername=;
$username=;
$password=;
$database=;
$strSql=;
$conn=mssql_connect("$servername","$username","$password");
mssql_select_db("$database", $conn);
$result=mssql_query($strSql,$conn);
$row=mssql_fetch_array($result)
echo $row[0]
?>