UPDATE: If code you posted doesn't work to do the update, I think I see why. When you create the LabEntry, you are setting -textvariable => \$user->{firstname}. Then when you retrieve from the database, you are saying: $user = $sth->fetchrow_hashref - which overwrites the the hashref $user you used in the LabEntry - if use use print "$user\n" before and after the the fetchrow_hashref, they should be different. This is the problem, to fix it, preserve $user by fetching to a different hashref, then say $user->{firstname} = $other->{firstname}.

This stuff is so cool. Having bound a variable to the -textvariable, you just change that variable and it automagically works:

#!/usr/bin/perl -w

use Tk;
my %User = ( firstname=>'bob' );
my $user = \%User;

my $mw = MainWindow->new();

     my $lbe = $mw->LabEntry(-label => "First Name",
           -labelPack => [-side => "left", -anchor => "w"],
           -width => 20,
           -textvariable => \$user->{firstname})->pack(-side => "top",
               -anchor => "ne");

my $btn = $mw->Button(-command=> sub { $user->{firstname} = ''. localt
+ime})->pack;

MainLoop;
[download]

Run it, click the button, be suitably impressed ;-P

--Bob Niederman, http://bob-n.com