It also ignores operations of type (set of rows) => (set of rows) or (row) => (set of rows). and makes you jump through hoops of CTEs to implement them except i

It also ignores operations of type (set of rows) => (set of rows) or (row) => (set of rows). and makes you jump through hoops of CTEs to implement them except in some special cases. Limited versions of these (flatMaps) work just fine in spark and have no problems scaling.