Re: Oversight in reparameterize_path_by_child leading to executor crash

Richard Guo <guofenglinux@gmail.com> writes:
> How about the attached v12 patch?  But I'm a little concerned about
> omitting PVC_RECURSE_AGGREGATES and PVC_RECURSE_WINDOWFUNCS in this
> case.  Is it possible that aggregates or window functions appear in the
> tablesample expression?

No, they can't appear there; it'd make no sense to allow such things
at the relation scan level, and we don't.

regression=# select * from float8_tbl tablesample system(count(*));
ERROR:  aggregate functions are not allowed in functions in FROM
LINE 1: select * from float8_tbl tablesample system(count(*));
                                                    ^
regression=# select * from float8_tbl tablesample system(count(*) over ());
ERROR:  window functions are not allowed in functions in FROM
LINE 1: select * from float8_tbl tablesample system(count(*) over ()...
                                                    ^

I pushed v12 (with some cosmetic adjustments) into the back branches,
since we're getting close to the February release freeze.  We still
need to deal with the larger fix for HEAD.  Please re-post that
one so that the cfbot knows which is the patch-of-record.

            regards, tom lane