I’ve downloaded WIPmania’s worldip table from http://www.wipmania.com/en/base/ — the table has 3 fields and around 79k rows:
- startip // example: 3363110912
- endip // example: 3363112063
- country // example: AR (Argentina)
So, lets suppose i’m in Argentina and my IP address is: 200.117.248.17
1) I use this function to convert my ip to long
function ip_address_to_number($ip) {
if(!$ip) {
return false;
} else {
$ip = split('\.',$ip);
return($ip[0]*16777216 + $ip[1]*65536 + $ip[2]*256 + $ip[3]);
}
}
2) I search for the proper country code by matching the long converted ip:
$sql = 'SELECT * FROM worldip WHERE '.ip_address_to_number($_SERVER['REMOTE_ADDR']).' BETWEEN startip AND endip';
which is equivalent to:
SELECT country FROM worldip WHERE 3363174417 BETWEEN startip AND endip (benchmark: Showing rows 0 – 0 (1 total, Query took 0.2109 sec))
Now comes the real question.
What if another bunch of argentinian guys also open the website and they all have these ip addresses:
- 200.117.248.17
- 200.117.233.10
- 200.117.241.88
- 200.117.159.24
Since i’m caching all the sql queries; instead of matching EACH of the ip queries in the database, would it be better (and right) just to match the 2 first sections of the ip by modifying the function like this?
function ip_address_to_number($ip) {
if(!$ip) {
return false;
} else {
$ip = split('\.',$ip);
return($ip[0]*16777216 + $ip[1]*65536);
}
}
(notice that the 3rd and 4th splitted values of the IP have been removed).
That way instead of querying these 4 values:
- 3363174417
- 3363170570
- 3363172696
- 3363151640
…all i have to query is: 3363110912 (which is 200.117.0.0 converted to long).
Is this right? any other ideas to optimize this process?
Do you absolutely have to use WIPmania? if not, Maxmind offers an open source solution: http://www.maxmind.com/app/geolitecountry. The advantage is that it’s a binary file, and there’s a PHP extension (you’d have to compile it ans install it). Used it on a couple of projects, the lookups are blazing fast. You can get the PCL extension here:
http://pecl.php.net/package/geoip