in reply to Hash throws out duplicate values

If you don't want to lose records, stop overwriting them. 
$s = 123;
$s = 456;
print "$s\n";  # 456

$a[1] = 123;
$a[1] = 456;
print "$a[1]\n";  # 456

$h{foo} = 123;
$h{foo} = 456;
print "$h{foo}\n";  # 456

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Maybe what you want is an hash of arrays? 
push @{ $h{$k} }, 123;
push @{ $h{$k} }, 456;
print "$_\n" for @{ $h{$k} };  # 123, 456

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Re^2: Hash throws out duplicate values
by spickles (Scribe) on Oct 12, 2009 at 08:56 UTC

    I was going to use a hash of arrays, but that will get messy real quick. So how would I use a while loop to connect to my database and populate each record of the hash? Here's my current code:

    while (my $records = $query_handle->fetchrow_hashref) {
        my $new_name     = $records->{'ap_name'};
        my $location     = $records->{'building'};
        my $first_name   = $records->{'primary_name'};
        my $first_ip     = $records->{'primary_ip'};
        my $second_name  = $records->{'secondary_name'};
        my $second_ip    = $records->{'secondary_ip'};
        my $third_name   = $records->{'tertiary_name'};
        my $third_ip     = $records->{'tertiary_ip'};
        my $group        = $records->{'bldg_short'};
        my $five_channel = $records->{'five_channel'};
        my $configured   = $records->{'configured'};
        my $mac_name     = $records->{'mac_name'};

#Add each element as a hash to an Array of Hashes (AoH)
        my $new_hash = {
            new_name => $new_name,
            location => $location,
            first_name => $first_name,
            first_ip => $first_ip,
            second_name => $second_name,
            second_ip => $second_ip,
            third_name => $third_name,
            third_ip => $third_ip,
            group => $group,
            five_channel => $five_channel,
            configured => $configured,
            mac_name => $mac_name
        };
        push (@aps, $new_hash);
    }

    [download]

    Can I step through the array 'records' and enter unique records using a loop with $i? I don't know where to place the $i to make it work.

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[d/l]

      What's the key? Do you even need a hash? You haven't said what you're trying to do.

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      I am curious, when I look at your input, I see 11 comma separated fields. When I look at your hash record field names, I see 12. Where did 'ap_name' go to or rather where could it come from? There seems to be a field missing. Perhaps I am blind and/or am miscounting. Either thing could be! I am also curious as to why you wouldn't use the same $var name as the hash key, ie, instead of my $new_name = $records->{'ap_name'}; Why not my $ap_name = $records->{'ap_name'} ?
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        What I'm trying to do is pull records from a database that has information about how an access point should be configured. I wanted to read that data into an array of hashes so that I could then step through each of the elements and repeat the commands I would type at the command prompt to configure them and automate the process. The reason for the use of $new_name and $old_name is so that during the automation process I can keep track of which variable I am using. When the database info is imported, the ap name is the new one it needs to be changed to. I run a different sub to query the ap for its old name, which happens to be the default name it boots up with. Then, to change its name, I issue the command 'config ap name <new> <old>' So, as I said, I thought an array of hashes would be the ticket, and that I would then just step through the array and duplicate all of my cli commands.

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