GridFieldOrderableRows::populateSortValues PHP Method

    protected function populateSortValues(DataList $list)
    {
        $list = clone $list;
        $field = $this->getSortField();
        $table = $this->getSortTable($list);
        $clause = sprintf('"%s"."%s" = 0', $table, $this->getSortField());
        $additionalSQL = !$list instanceof ManyManyList ? ', "LastEdited" = NOW()' : '';
        foreach ($list->where($clause)->column('ID') as $id) {
            $max = DB::query(sprintf('SELECT MAX("%s") + 1 FROM "%s"', $field, $table));
            $max = $max->value();
            DB::query(sprintf('UPDATE "%s" SET "%s" = %d%s WHERE %s', $table, $field, $max, $additionalSQL, $this->getSortTableClauseForIds($list, $id)));
        }
    }