$sth_get_branch_list = $dbh->prepare(qq(
                        SELECT branch FROM postgres_database WHERE tree = 'first_tree'
                        AND branch ~ '$root.\\\\d+';
                        ));

##</code><code>##

$sth_get_branch_list = $dbh->prepare(q(
                        SELECT branch FROM postgres_database WHERE tree = 'first_tree'
                        AND branch ~ ? || '.\\\\d+';
                        ));