code: func (la *LogicalApply) canPullUpAgg() bool {
  	if la.JoinType != InnerJoin && la.JoinType != LeftOuterJoin {
  		return false
  	}
  	if len(la.EqualConditions)+len(la.LeftConditions)+len(la.RightConditions)+len(la.OtherConditions) > 0 {
  		return false
  	}
  	return len(la.children[0].Schema().Keys) > 0
  }
docs: // canPullUpAgg checks if an apply can pull an aggregation up.