The reason it's not working is because you're creating a reference to exactly the same variable each time (because @temp is global instead of lexical).

What you should do, is change @temp to be a lexical variable, scoped to the body of the while loop. That way, a new lexical variable will be created each time, and the reference that you stored away in the hash will keep all the old lexical variables alive (but anonymous). Like so:

open(PARMFILE, "< $parmfile")
  or die "unsuccessful open of input file $parmfile";
while (<PARMFILE>) {
  next if /^#/ || /^\s*$/;
  chomp;
  my @temp=split(/\s+/,$_);     # Note the 'my'
  $dbparms{$temp[2]} = \@temp;
}
close PARMFILE;

foreach $item (sort keys %dbparms) {
  print "$item => $dbparms{$item} \n";
}
[download]

And that should get the effect you want.

Update: I tested it, and it does work, although your print loop doesn't dereference the array-ref so you just get a bunch of lines like: '01 => ARRAY(0x1accdcc)'. Change the print loop to the following for a more useful output ;-)

foreach $item (sort keys %dbparms) {
  $" = ',';
  print "$item => @{$dbparms{$item}} \n";
}
[download]

bbfu
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