Re: [sqlsmith] Failed assertion in parallel worker (ExecInitSubPlan)

create or replace function parallel_func_select() returns integer

as $$

declare

    ret_val int;

begin

     ret_val := 1000;

     return ret_val;

end;

$$ language plpgsql Parallel Restricted;

CREATE TABLE t1(c1, c2) AS SELECT g, repeat('x', 5) FROM

generate_series(1, 10000000) g;

CREATE TABLE t2(c1, c2) AS SELECT g, repeat('x', 5) FROM

generate_series(1, 1000000) g;

From the above output it is clear that parallel restricted function is pushed down below gather node.  I found that though we have have care fully avoided to push pathtarget below GatherPath in apply_projection_to_path() if pathtarget contains any parallel unsafe or parallel restricted clause, but we are separately also trying to apply pathtarget to partialpath list which doesn't seem to be the correct way even if it is required.  I think this has been added during parallel aggregate patch and it seems to me this is not required after the changes related to GatherPath in apply_projection_to_path().

After applying the attached patch, it avoids to add parallel restricted clauses below gather path.

Now back to the original bug, if you notice in plan file attached in original bug report, the subplan is pushed below Gather node in target list, but not to immediate join, rather at one more level down to SeqScan path.  I am still not sure how it has manage to push the restricted clauses to that down the level.

Thoughts?