データベースへの接続+データ処理を学ぶPHP

$conn=mysql_connect("10.0.10.0:0000","root","123456") or die("数据库连接失败").mysql_error();//连接数据库
mysql_select_db("database");
$querry1 = "SELECT * FROM `crm_module_27` where field1='" . $ORDER_ID . "'";     
$cursor1 = mysql_query($querry1);
if ($ROW = mysql_fetch_array($cursor1)) {
         $startwork=$ROW['field3'];
}
$now=date("Y-m-d");//日期处理
$nowy=date("y");
 
$nowy1=date("y",strtotime("-1 year"));
$nowy2=date("y",strtotime("+1 year"));
$nowm=date("m");
$nowm1=date("m",strtotime("-1 month"));
$nowm2=date("m",strtotime("+1 month"));
$nowd=date("d");
$startworky=date("y",strtotime($startwork));
$startworkm=date("m",strtotime($startwork));
$startworkd=date("d",strtotime($startwork));