While the trick is nice for some purposes, note this doesn't yield up what the poster asked for. What you get out of your procedure, for each row, is a hash reference that looks like:

#col1name and col2name are the names of the columns in the database
$hash_ref = { col1name=>"orange",
              col2name=>"15" };
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But the poster wants to (essentially) turn a two-D array (which is what the result set is) into a hash, with the keys coming from column 1 and the values coming from column 2. While I'm here, thought I'd post something which is a little wacky, and probably less easily understood that Masem's answer (or my earlier one) but that illustrates what the poster wanted:

# get whole result set into an array

my @rs = @{ $sth->fetchall_arrayref() };

# each element of @rs is a reference to a two-member array

#let's map the first elements to the keys of the hash
# and the second elements to the values.
my %hash = map { $_->[0] => $_->[1] } @rs;
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OK, I'll cop to listening to Van Halen on the internet radio, so I had to execute a little guitar-solo.

perl -e 'print "How sweet does a rose smell? "; chomp ($n = <STDIN>); 
+$rose = "smells sweet to degree $n"; *other_name = *rose; print "$oth
+er_name\n"'
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