code: func PercentileContIntervalFinal(db XODB, v0 pgtypes.Internal, v1 float64) (*time.Duration, error) {
  	var err error
  
  	// sql query
  	const sqlstr = `SELECT pg_catalog.percentile_cont_interval_final($1, $2)`
  
  	// run query
  	var ret *time.Duration
  	XOLog(sqlstr, v0, v1)
  	err = db.QueryRow(sqlstr, v0, v1).Scan(&ret)
  	if err != nil {
  		return nil, err
  	}
  
  	return ret, nil
  }
docs: // PercentileContIntervalFinal calls the stored procedure 'pg_catalog.percentile_cont_interval_final(internal, double precision) interval' on db.