Hi,
while working on [1] (works, harmless regression check failures aside,
needs cleanup), I noticed $subject. Without fixing EXPR_KIND_VALUES to
set p_hasTargetSRFs the query has Query->hasTargetSRF wrongly set.
Which in turn breaks your planner code, as it's not being triggered
anymore.
Is there a reason not to just set p_hasTargetSRFs once towards the end
of the function, instead of doing so for all the non-error cases? That
fixes INSERT ... VALUES(generate_series()) with your approach for me.
I also noticed that we currently don't actually handle
Query->hasTargetSRF correct when said SRF is in a VALUES() block. As
there the SRFs are't in the targetlist
PlannerInfo *
subquery_planner(PlannerGlobal *glob, Query *parse, PlannerInfo *parent_root, bool
hasRecursion,double tuple_fraction)
.../* Constant-folding might have removed all set-returning functions */if (parse->hasTargetSRFs)
parse->hasTargetSRFs= expression_returns_set((Node *) parse->targetList);
unsets that SRFs exist. I'm not really sure whether that's bad or good
- it right now doesn't cause active problems because of
transformInsertStmt's /* * Process INSERT ... VALUES with a single VALUES sublist. We treat * this case
separatelyfor efficiency. The sublist is just computed * directly as the Query's targetlist, with no VALUES RTE.
Soit * works just like a SELECT without any FROM. */
optimization.
As we don't support SRFs in any other kind of values (ValuesNext calls
ExecEvalExpr isDone = NULL), that appears to be effectless right now.
But we'd get better errormessage if we made check_srf_call_placement()
error out. I wonder if there should be a seperate expression type for
the INSERT ... VALUES(exactly-one-row); since that behaves quite
differently.
Greetings,
Andres Freund
[1] http://archives.postgresql.org/message-id/20170116032952.z2re55hcfhzbkmrm%40alap3.anarazel.de