well if you can afford to store the data in memora this could work for you

use strict;


my @array;

while(<DATA>){
    chomp;
    my @arr = split(',',$_);
    push (@array,\@arr);
}
@array = sort{$a->[1] cmp $b->[1]}@array;
foreach (@array){
    print "@$_ \n";
}

__DATA__
miki,maus,kiki
sis,miki,misi
nick,pick,flick
amico,aco,taco
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