userName is an array value, not a key. Assuming you mean the element in the table array that has the same index as the element in columns with the value 'userName', you'd need something like: 

#!/usr/bin/perl
use strict;
use warnings;

my $VAR1 = {
          'table' => [
                     [
                       'CredSMB.168',
                       '168',
                       '1',
                       'Customer.1',
                       '',
                       'BNS-NA-CA-SMB-SCGLOBAL',
                       '3',
                       'SCGLOBAL',
                       'ip360scglobal'
                     ]
                   ],
          'columns' => [
                       'REFERENCE',
                       'id',
                       'type',
                       'customer',
                       'notes',
                       'name',
                       'authAlgorithm',
                       'domain',
                       'userName'
                     ]
        };
foreach my $i (0 .. $#{$VAR1->{columns}}) {
    if ($VAR1->{columns}[$i] =~ /^userName$/) {
        print "$VAR1->{table}[0][$i]\n";
    }
}

[download]

See perlref, perlreftut, perllol and/or perldsc for some refreshers.

In reply to Re: help me interpret Dumper output. by kennethk
in thread help me interpret Dumper output. by rbaldwin

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