php连接数据库的四种方法

<?php
$conn = new Com("ADODB.Connection"); //实例化一个Connection对象
$connstr = "provider=sqloledb;datasource=.;uid=用户名;pwd=密码;database=数据库;";
$conn->Open($connstr);
$rs = new Com("ADODB.Recordset"); //实例化一个Recordcount对象
/*使用实例*/
$rs->Open('select * from News where bigclassid = 59 And LeadPostil is null', $conn, 1, 1);
$count = $rs->RecordCount; // www.jb200.com
echo "共有{$count}条纪录<br />";
for($i = 0; $i < $count ; $i++){

$arr_result[$i]['Title'] = addslashes($rs->Fields('Title')->Value);//标题
$arr_result[$i]['Color'] = addslashes($rs->Fields('titlecolor')->Value?$rs->Fields('titlecolor')->Value:'');//标题颜色
$arr_result[$i]['WenHao'] = addslashes($rs->Fields('OtherText')->Value);//文号
}

<?php
$dbhost = '';
$dbuser = ''; //你的mssql用户名
$dbpass = ''; //你的mssql密码
$dbname = ''; //你的mssql库名

$connect=odbc_connect("Driver={SQL Server};Server=$dbhost;Database=$dbname","$dbuser","$dbpass");
/*实例测试*/
$sql="select * from content";
$exec=odbc_exec($connect,$sql);
while($row = (odbc_fetch_array($exec)))
{
$row['id'] //獲取字段值
...
}

<?
$dbh=mysql_connect("主机名","用户","密码");
mssql_select_db("mydb", $dbh);
?>

<?php
$db=$_SERVER['DOCUMENT_ROOT']."/PHP_ACCESS/include/#mydb.mdb"; //這裏最好用$_SERVER['DOCUMENT_ROOT']获取路径
$conn = new COM('ADODB.Connection') or die('can not start Active X Data Objects');
$conn->Open("DRIVER={Microsoft Access Driver (*.mdb)}; DBQ=$db");
$rs = $conn->Execute('SELECT * FROM contents order by id desc');
while(!$rs->EOF)
{
echo $rs->Fields['name']->Value;
$rs->MoveNext();
}
/*释放资源*/
$rs->Close();
$conn->Close();
$rs = null;
$conn = null;