Dean Rasheed <dean.a.rasheed@gmail.com> writes:
> Here's an updated patch, now with test cases involving both OLD and
> NEW references.
It might be worth doing
+ if (rte->rtekind == RTE_SUBQUERY && !rte->lateral &&
+ contain_vars_of_level((Node *) rte->subquery, 1))
+ rte->lateral = true;
so as to save the expense of contain_vars_of_level() when the flag
is already set. However, it's arguable that no users would bother
with writing LATERAL, so this might be pointless.
More importantly, I think the comment could do with a bit more
information. Maybe like
/*
+ * Mark any subquery RTEs in the rule action as LATERAL if they contain
+ * Vars referring to the current query level (references to NEW/OLD).
+ * Those really are lateral references, but we've historically not
+ * required users to mark such subqueries with LATERAL explicitly.
+ * But the planner will complain if such Vars exist in a non-LATERAL
+ * subquery, so we have to fix things up here.
+ */
That might be overly verbose, but I think it's good to memorialize this
sort of info.
LGTM otherwise.
regards, tom lane
