code: func PgSleepUntil(db XODB, v0 time.Time) error {
  	var err error
  
  	// sql query
  	const sqlstr = `SELECT pg_catalog.pg_sleep_until($1)`
  
  	// run query
  	XOLog(sqlstr)
  	_, err = db.Exec(sqlstr)
  	return err
  }
docs: // PgSleepUntil calls the stored procedure 'pg_catalog.pg_sleep_until(timestamp with time zone) void' on db.