use strict;
use warnings;

my @valueNames = qw/major minor revision/;
my %oldVersions = (
    aht => {major => 8, minor => 3, revision => 6},
    dog => {major => 3, minor => 3, revision => 1},
    );
my %versionEdits = (
    aht => {major => 9, minor => 4, revision => 0},
    dog => {revision => 2},
    );

for my $version (sort keys %versionEdits) {
    my %values;
    
    $values{$_} = $oldVersions{$version}{$_} for @valueNames;
    for my $edit (sort keys %{$versionEdits{$version}}) {
        my $newValue = $versionEdits{$version}{$edit};
        
        print "Update $version set $edit = $newValue #DBVersion ";
        print join '.', @values{@valueNames};
        print "\n";
        $values{$edit} = $newValue;
    }
}