code: func ClockTimestamp(db XODB) (time.Time, error) {
  	var err error
  
  	// sql query
  	const sqlstr = `SELECT pg_catalog.clock_timestamp()`
  
  	// run query
  	var ret time.Time
  	XOLog(sqlstr)
  	err = db.QueryRow(sqlstr).Scan(&ret)
  	if err != nil {
  		return time.Time{}, err
  	}
  
  	return ret, nil
  }
docs: // ClockTimestamp calls the stored procedure 'pg_catalog.clock_timestamp() timestamp with time zone' on db.