src/Rentgen/Database/Constraint/PrimaryKey.php
public function getColumns()
    {
        return empty($this->columns)
            ? $this->table->getName() . '_id'
            : implode(',', $this->columns);
    }
public function getColumns()
    {
        return empty($this->columns)
            ? $this->table->getName() . '_id'
            : implode(',', $this->columns);
    }
TODO hmmmmmm....