code: func outOfRange(sc *stmtctx.StatementContext, min, max, val *types.Datum) (int, error) {
  	result, err := val.CompareDatum(sc, min)
  	if err != nil {
  		return 0, err
  	}
  	if result < 0 {
  		return result, nil
  	}
  	result, err = val.CompareDatum(sc, max)
  	if err != nil {
  		return 0, err
  	}
  	if result > 0 {
  		return result, nil
  	}
  	return 0, nil
  }
docs: // outOfRange checks if the `val` is between `min` and `max`.