You haven't told us what __DATA__ you have or what data structure you want out at the end of it!

If you put the input as tab delimited text so people can repeat the read in of data and give us an actual data structure you want to get to ( either in words i.e. hash of hashes, or as example code like the output of Data::Dumper ), we may be able to help you better!

Thanks BioLion

You are absolutely correct. I've updated my post with __DATA__


Blackadder

OK, but I am still struggling a little bit - what is the actual contents of @Colum_A?:

use Data::Dumper qw/Dumper/;

my $xls_path = "c:/path_to_xls.xlsx";
my $xls = $excel->Workbooks->Open("$xls_path");     

foreach my $sheet ( in $xls->Worksheets ) 
{
    $San ={};
    $San->{name} = $sheet->Name, $/;    
    
    my $San_data = $xls->Worksheets("$San->{name}");
    my @Colum_A = $San_data->UsedRange->{'Value'};

    ## what datastructure are we working with?
    print "SAN : $San->{name}\n";
    print Dumper \@Colum_A;
}
[download]

If it is a long array like you say then why not take a simple approach?:

use strict;
use warnings;
use Data::Dumper qw/Dumper/;

#my $xls_path = "c:/path_to_xls.xlsx";
#my $xls = $excel->Workbooks->Open("$xls_path");
## just for testing
my $xls = [qw/san1 san2/];  
my $data;
#foreach my $sheet ( $xls->Worksheets ){
for my $sheet ( @$xls ){
    print "Data in SAN : $sheet\n";
    ## store each san as a hashref
    my $San ={};
    #$San->{name} = $sheet->Name, $/;
    $San->{name} = $sheet;
    
    #my $San_data = $xls->Worksheets("$San->{name}");
    #my @Colum_A = $San_data->UsedRange->{'Value'};
    
    ## again, just for testing
    my @Colum_A = qw/    RDUB010
                        34:34:36:7U
                        87:23:89:6C

                        RDUB090
                        90:39:12:6U
                        34:34:36:7Z
                        87:23:89:6N
                        34:38:36:7U
                    /;

    ## process each array element and print something appropriate
    ## also store data into a HoH / HoA
    my $current = 'not_defined'; # place holder
    foreach my $element (@Colum_A){
        if ($element =~ /^RD/){
              print "\tSAN : $San->{name}\n\t - LUN : $element\n";
              $current = $element;
        }
        elsif ( $element =~ /^(?:[^:]{2}:){3}[^:]{2}$/){
              # untested! should match
              # 60:05:08:b2:00:bb:b6:93
              print "\t\tWW : $element\n";
              push @{ $San->{LUN}->{$current} }, $element;
        }
        else {
            warn "Unrecognised input : \'$element\'\n";
        }
    }
    ## add San to data
    push @$data, $San;
}
## print out data structure
print "\n-----> DATA\n";
print Dumper $data;
## and again
print "\n-----> OUTPUT\n";
foreach my $san (@$data){
    print "SAN : $san->{name}\n";
    foreach my $lun( keys %{ $san->{LUN} } ){
        print " - LUN : $lun\n";
        print "\tWW : $_\n" for @{ $san->{LUN}->{$lun} }
    }
}
[download]

This produces what you seem to be looking for:

Read more... (2 kB)

Update bugfixed code... Note to self - DO NOT POST UNTESTED REGEXES...

Just a something something...