Well, there's the simple answer of just use push (push @{$VAR1}, @{$VAR2}), but that's ignoring the fact that's only a shallow copy of the constituent arrayrefs and that you'll be able to diddle (say) $VAR2->[1]->[1] and affect the value you see as $VAR1->[2]->[1]. If that's an issue you'd want to iterate over @{ $VAR2 } and push copies instead (push @{$VAR1}, [ @{ $_ } ] for @{ $VAR2 }). Or use something like Storable's dclone routine to do a deep clone of $VAR2 and use the first push solution.

If you want to deep copy one of them and push it onto the other one, these might help:

• deep copy of nested data structure
• deepcopy
• perlfaq4: How do I print out or copy a recursive data structure?

It is helpful to remember that your Array of Arrays is just an array of references. So it is only necessary to pop the references from one and push them on to the other. There is no need to copy the actual data. This:

push @$VAR1, pop @$VAR2;

... moves one array from VAR2 into VAR1. You can extend that with a simple map or foreach

Thanks all for the replies! Ok, like apl says, maybe i should be a bit more specific :) Let me explain the scenario first... I am building a PDF from data that I extract from a DB. When the data gets retrieved via a DBI fetchall_arrayref, it only returns the data like it should. The problem is that I am using PDF::Table. I need to add a header row to the array cause PDF::Table auto repeats the first row as a header if the data spans more than 1 page. So keeping that in mind this is the scenario:

...
use Data::Dumper;
...
my @ref_header = ( 
       [ ["Name", "Surname"] ],
    );
...
@ref_db_data = $sth->fetchall_arrayref;
[download]

the data that is in @ref_db_data is:

print Dumper @ref_db_data;
$VAR2 = [
          [
            'John',
            'Doe'
          ],
          [
            'Jane',
            'Smith'
          ],
        ];
[download]

What I want to do is joint (merge) the two arrays to simply add the header row so that I can then print it on the PDF. Hope this makes sense... :P

Your @ref_db_data is going to be a one-element array with an array reference as that one element. There's nothing wrong with that, but it might not be what you really want.

I'm guessing what you're shooting for is this:

my $ref_header = [ 'Name', 'Surname' ];
my @ref_db_data = @{ $sth->fetchall_arrayref };
unshift @ref_db_data, $ref_header;
[download]

Or maybe this:

my $ref_header = [ 'Name', 'Surname' ];
my $ref_db_data = $sth->fetchall_arrayref;
unshift @{ $ref_db_data }, $ref_header;
[download]

Here's your original situation:

my @ref_header = ( 
       [ ["Name", "Surname"] ],
    );
...
@ref_db_data = $sth->fetchall_arrayref;
unshift @{$ref_db_data[0]}, $ref_header[0]->[0];
[download]

...but I'm not sure if that's what you're shooting for. You wind up with something like:

@ref_db_data = ( [ [ 'Name', 'Surname' ],
                   [ 'John', 'Doe'     ],
                   [ 'Jane', 'Smith'   ]
                 ]
               );
[download]