Re: BUG #17088: FailedAssertion in prepagg.c

Andrew Gierth <andrew@tao11.riddles.org.uk> writes:
> A number of places in the planner have to explicitly avoid recursing
> into GroupingFunc->args when walking trees specifically because they are
> not evaluated. It looks to me like some places where that should have
> been checked for were missed. Looking into it.

Hmm.  Maybe it'd be better if the default behavior in
expression_tree_walker/mutator did not include recursing into the args,
then?  I am thinking this might be comparable to SubLinks/SubPlans, where
the walker has to take explicit action if it wants to recurse into the
sub-query.

            regards, tom lane