sub inflate
{
    my ($results) = @_;

    my %data;

    foreach my $results (@$results)
    {
        my ($mag, $issue, $article) = @{$results}{qw( mag_name issue_n
+um article )};
        push @{$data{$mag}{$issue}}, $article;
    }

    foreach my $mag (keys %data)
    {
        $data{$mag}{article_loop} = map {
            issue_number => $_,
            article_loop => $data{$mag}{$_},
        } keys %{$data{$mag}};
    }

    return \%data;
}
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It doesn't preserve the order the issues for each magazine came back from the database, but sorting should be a view question, not a data retrieval question.