PHP code once per IP Address

<?php
//note: you must make a table in your
//database called ips with a field called ipaddress
//
//set your mysql options here
$sqlserver = "localhost";
$sqluser = "yourMySqlUsername";
$sqlpassword = "yourMysqlPass";
$sqldatabase = "YourMysqlDB-name";
//end mysql settings

mysql_connect($sqlserver, $sqluser, $sqlpassword);
mysql_select_db($sqldatabase) or die(mysql_error() );

$ip=$_SERVER['REMOTE_ADDR'];

$ipsearch = mysql_query("SELECT * FROM ips WHERE `ipaddress` = '$ip'");

if(mysql_num_rows($ipsearch) < 1){

  //
  //Run your script here.
  //
  
  mysql_query("INSERT INTO ips (`ipaddress`) VALUES('$ip') ");
}

?>