uses uMMDBReader;

var
  LMMDBReader: TMMDBReader;
  LIPAddress: TMMDBIPAddress;
  LIPInfo: TMMDBIPCountryInfo;
  prefixLength: Integer;
begin
 LIPInfo := TMMDBIPCountryInfo.Create;
 LMMDBReader := TMMDBReader.Create('C:\GeoIP2\GeoLite2-Country.mmdb');
 try
   LIPAddress := TMMDBIPAddress.Parse('8.8.8.8');
   if LMMDBReader.Find<TMMDBIPCountryInfo>(LIPAddress, prefixLength, LIPInfo) then
     ShowMessage(Format('country_iso_code: "%s", country_geoname_id: %s', [LIPInfo.Country.ISOCode, IntToStr(LIPInfo.country.GeonameId)]))
   else
     ShowMessage('Not found');
 finally
   LMMDBReader.Free;
   LIPInfo.Free;
 end;
end;