Your hash creation should look like this: 
    %LdnLine = ($j => \@check2);

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The value must be a reference, not an actual array.

To answer your second question--why does it look right when you print out the entire hash--that's because your array is being treated as a list to initialize the hash. It's not treated as an array value to your key $j; the values in @check2 are used as both keys and values in your hash. This is more clear if you do this: 

    use Data::Dumper;
    print Dumper \%LdnLine;

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With my dummy values for @check2 and $j this gave me 
    $VAR1 = {
              1 => 'foo',
              'bar' => 'baz'
            };

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Which, I'll bet, is not what you were expecting.

In reply to Re: Using an array in a hash by btrott
in thread Using an array in a hash by Anonymous Monk

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