Problem background is that we have a file that contains logs of data for error codes, and my boss now wants this to be tallied up into something that is useable for analysis. There are 3 basic pieces of information that need to be tallied :

Country
Error code
Message Type

The requirement is to be able to produce a report at anytime from this file to show the number of errors per Message type per error code per country, as well as the number of errors per Message type per country per error code.

My immediate thought was to do a 3 dimensional hash as it would be indexed and therefore should be easier to manipulate and handle. However, I am really struggling to determine how to define the hash below the 2nd level.

For example for the first scenario:
  %hash=("$country"=>{
             "$errorcode=>{
         $messagetype=>{                         "count"=>"value"}}})

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Then to check for existence of a key it would be :
if (defined $hash{$country}{$errorcode}{$message}{$count})
    {
    $hash{$country}{$errorcode}{$message}{$count}+=1;
    }
    else
    {
    $hash{$country}{$errorcode}{$message}{$count}=1;
    }

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Then we get onto the problem of printing the darn thing. 
for $varctry(keys %hash)
{
  for $varerror(@$hash{$varctry})
  {
  for $varmsgtype(@$hash{$varctry}{$varerror})
    {
    print "Country $varctry with error $varerror for msg $varmsgtype h
+as $hash{$varctry}{$varerror}{$varmsgtype}{count} errors\n";
        }
  }
}

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I have tried various combinations, but a lot of the time I am getting warnings back saying that I do not have even amounts of values in my hash, meaning that I don’t have a straight key to value relationship, so I must be missing something obvious here! Any tips you have for me would be greatly appreciated.
Thank you in advance.

In reply to 3 dimensional hashes! by mark_briscombe

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