# Bredth first listing of all nodes under given root (incl. root).
#
my $get_children = sub {
  my $parents = \@_; # Hackery. We should really only accept one id.
  my @children;
  
  my $dbh = $DB->getDatabaseHandle;
  
  local $" = ',';
  
  while ( @$parents > 0 ) {
    push @children, @$parents;
    
    $parents = $dbh->selectcol_arrayref(qq{
      SELECT note_id
        FROM note
       WHERE parent_node IN ( @$parents )
    });
  }
  
  return @children; # Returns root at head of list (easier later ;)
}


# Runs a search and replace on the title of selected nodes. Returns
# number of records updated (0 still true).
#
my $retitle = sub {
  my $new_title = shift;
  my $old_title = shift;
  my @nodes     = @_;
  
  my $dbh = $DB->getDatabaseHandle;
  
  local $" = ',';

  $dbh->do(qq{
    UPDATE note
       SET title = REPLACE(title, ? , ?)
     WHERE note_id IN( @nodes )
    }, undef, ($old_title, $new_title)
  );
}



my $id = getId($NODE);

$retitle_nodes->( 'new_title_var_goes_here', getNodeById($id)->{title}, $get_children->($id) );