-------------------------------------------------------------------------
function PostZapros(url:string; zapros:string):string;
var IdHTTP:TIdHTTP; list:TStringList;
begin
       IdHTTP:=TIdHTTP.Create(nil);
       list:=TStringList.create;
       list.add(zapros);
       result:=IdHTTP.POST(url,list);
       IdHTTP.Free;
       list.Free;
end;
----------------------------------------------------------------------
procedure Tf.SpeedButton1Click(Sender: TObject);
begin
      f.Memo1.Text:=PostZapros('http://z9_client.ru/comn.php','xxx=kaka');
end;

----------------------------

comn.php:

<?php
       if($_POST['xxx']=="kaka"){echo 'nea';}
?>

------------------------------------------------------------------
if (isset($_POST['zapros']) && !empty($_POST['zapros'])){
//mysql settings

     $sqlmain = array();
     $sqlmain['database'] = 'database';
     $sqlmain['host'] = '127.0.0.1';
     $sqlmain['user'] = 'root';
     $sqlmain['pass'] = 'password';

     $connect = mysql_connect($sqlmain['host'],$sqlmain['user'],$sqlmain['pass']) or die('nosqlmainconnect');
     mysql_select_db($sqlmain['database'], $connect);
     mysql_set_charset('utf8', $connect);
//Действие со скулей.
     mysql_close($connect);
} else {
echo '404 Not Found';
}