code: func updateDBVersion(tx *sql.Tx, version int) error {
  	// ql doesn't have an INSERT OR UPDATE function so
  	// it's faster to remove and reinsert the row
  	_, err := tx.Exec("DELETE FROM version")
  	if err != nil {
  		return err
  	}
  	_, err = tx.Exec("INSERT INTO version VALUES ($1)", version)
  	if err != nil {
  		return err
  	}
  	return nil
  }
docs: // updateDBVersion updates the db version