code: func matchItems(p *property.PhysicalProperty, items []*ByItems) bool {
  	if len(items) < len(p.Items) {
  		return false
  	}
  	for i, col := range p.Items {
  		sortItem := items[i]
  		if sortItem.Desc != col.Desc || !sortItem.Expr.Equal(nil, col.Col) {
  			return false
  		}
  	}
  	return true
  }
docs: // Check if this prop's columns can match by items totally.