function db_array_to_update_sqladd($arr) {
$s = '';
foreach ($data as $k => $v) {
    $op = substr($k, -1);
    if ($op == '+' || $op == '-') {
        $k = substr($k, 0, -1);
        $v = (is_int($v) || is_float($v)) ? $v : "'" . addslashes($v) . "'";
        $s .= "`$k`=`$k`$op$v,";
    } else if ($op == '=') {
        $k = substr($k, 0, -1);
        $s .= "`$k`=`$v`,";
    } else {
        $v = (is_int($v) || is_float($v)) ? $v : "'" . addslashes($v) . "'";
        $s .= "`$k`=$v,";
    }
}
return substr($s, 0, -1);
}