hash-value-overwrite-due-to-similar-keys.pl

#!/usr/bin/perl

# https://stackoverflow.com/questions/48529062/hash-value-overwrite-due-to-similar-keys

use Data::Dumper;

my $mapping_table = {
    'Exemplare' => 'copies',
    'Seiten' => 'pages',
    'Statushinweis' => 'status',
    'Serie von' => 'number_of',
    'ISBN/Barcode-Nr.' => 'ISBN_barcode',
    'Status' => 'status',
};

my $data = [
  {
    'Exemplare' => '1',
    'Seiten' => '0',
    'Statushinweis' => 'Statushinweis',
    'ISBN/Barcode-Nr.' => '3-551-01561-9',
    'Serie von' => '4',
    'Status' => 'Gesucht'
  },
  {
    'Exemplare' => '4',
    'Seiten' => '111',
    'Statushinweis' => '',
    'ISBN/Barcode-Nr.' => '3-551-01561-9',
    'Serie von' => '4',
    'Status' => 'Vorhanden'
  }
];

my $mapped_data = [];

foreach my $issue ( @$data ) {
    my %tmp_hash;
    foreach my $key (sort keys %$mapping_table) {
        $tmp_hash{$mapping_table->{$key}} = $issue->{$key};
    }
    push @$mapped_data, \%tmp_hash;
}

print Dumper $mapped_data;