This PR mainly prohibits operations such as aggregation/sorting/window functions
on lateral views containing subqueries.
For example:
select min(e1) from (select c1 from table group by c1)tmp1 lateral view explode_split(c1, ",") tmp2 as e1
But the query can be written in another way, and the result is the same.
select min(e1) from (select e1 from (select c1 from table group by c1)tmp1 lateral view explode_split(c1, ",") tmp2 as e1) tmp3
The reason is that when the results of a inline view are subjected to a lateral view,
and the outer query performs aggregation or sorting operations on non-table-function columns.
The output slot id of the table function node is empty or has fewer columns.
The essential reason is that when the inner layer contains an inline view,
the outer expression needs to be mapped to the correct tuple through the substitute method
according to the smap instead of the virtual tuple.
But the substitute method of slot ref cannot recurse to its own source exprs.
E.g
SlotRef: c2 <source expr min(c1)> from agg tuple
smap: <c1, c3>
before: c2 <source expr min(c1)>
after: c2 <source expr min(c1)> no changed
c873c8c162