If I am understanding you correctly, you could store each record in a HoHoHoA. For each record you read in, you would need the following psuedo code: 
   my $IP = #extract from %data;
   my $userAgent = #extract from %data;
   my $date = #extract from %data;
   my $aRequests = $hRequests{$IP}{$userAgent}{$date};
   push @$aRequests, \%data;

[download]

Then after you have read in all the requests, loop through %hRequests using the hash keys to select the requests that interest you. The pseudo code would look something like this:

   while (my ($IP, $hUserAgents) = each(%hRequests)) {
      next if #IP is boring;
      while (my ($userAgent, $hDates = each(%$hUserAgents)) {
          next if #user agent is boring;
          while (my ($date, $aRequests) = each(%$hDates)) {
             #do something if date is in range
             #wanted for $IP, $userAgent
          }
      }
   }

[download]

There's a lot of work navigating references to hashes and arrays here. As moritz said previously, studying perldata, perlref (or perlreftut) and perldsc might be well worth your time.

Best, beth

In reply to Re^3: Adding data to hashes & comparing by ELISHEVA
in thread Adding data to hashes & comparing by hallikpapa

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