my $toplevel = $mw->toplevel;
my $menubar = $toplevel->Menu(-type => 'menubar');

#I try to add
my $applemenu = $menubar->cascade(-label => '.apple');#or 'apple'

my $MenuDatabase = $menubar->cascade(-label => '~Database', -tearoff => 0);
$MenuDatabase->command(-label => "Perform query", -command => sub{PerformQuery()}, -compound => 'left');

$toplevel->configure(-menu => $menubar);