How to read in a file in perl, put it in a hash table, and then sort it by a hash value (not the key)

I have a file named list.txt. Inside that file are many rows that look like this.

GA_ZTC      CC_9811111
IA_ZTC      CC_9811112
IA_ZTC      CC_9711233

Each column is separated by a tab. I need to sort the list by the second column. I was trying to read it into a hash table and sort on the value, but my code is not working well. Ideally, at the end I would have a two column file sorted by the second column. I have thought about writing it out to another file, swapping columns, sorting it and then reordering it, but I think this is not efficient coding. I would appreciate it if somebody could help me figure out how to do this with a hash table. Thanks in advance.

#!/usr/bin/perl
# Read in a file and print it out.

# use strict;

open(INFILE, "Bld_Org2_S3.txt"); # open for input
open(OUTFILE,">","sortedlist.txt");

sub hashValueAscending
{
   $val{$a} cmp $val{$b};
}

my %hash;
while (<INFILE>)
{ 
   chomp; 
   my ($key, $val) = split /\t/;
   $hash{$key} .= exists $hash{$key} ? "$val" : $val;
   foreach $key (sort hashValueAscending (keys(%hash))) 
		{
			print OUTFILE $hash{$key}."\t".$key."\n";
		}
}

#flock(INFILE, LOCK_UN);
close(INFILE);
close(OUTFILE);

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