Re: [Bug] Inconsistent result for inheritance and FOR UPDATE.

(2014/12/12 10:37), Tom Lane wrote:
> Yeah, this is clearly a thinko: really, nothing in the planner should
> be using get_parse_rowmark(). I looked around for other errors of the
> same type and found that postgresGetForeignPlan() is also using
> get_parse_rowmark(). While that's harmless at the moment because we
> don't support foreign tables as children, it's still wrong. Will
> fix that too.

I don't think we need to fix that too. In order to support that, I'm
proposing to modify postgresGetForeignPlan() in the following way [1]
(see fdw-inh-5.patch).

*** a/contrib/postgres_fdw/postgres_fdw.c
--- b/contrib/postgres_fdw/postgres_fdw.c
***************
*** 824,834 **** postgresGetForeignPlan(PlannerInfo *root,
{
RowMarkClause *rc = get_parse_rowmark(root->parse, baserel->relid);

if (rc)
{
/*
! * Relation is specified as a FOR UPDATE/SHARE target, so handle
! * that.
*
* For now, just ignore any [NO] KEY specification, since (a) it's
* not clear what that means for a remote table that we don't have
--- 824,847 ----
{
RowMarkClause *rc = get_parse_rowmark(root->parse, baserel->relid);

+ /*
+ * It's possible that relation is contained in an inheritance set and
+ * that parent relation is selected FOR UPDATE/SHARE. If so, get the
+ * RowMarkClause for parent relation.
+ */
+ if (rc == NULL)
+ {
+ PlanRowMark *prm = get_plan_rowmark(root->rowMarks, baserel->relid);
+
+ if (prm && prm->rti != prm->prti)
+ rc = get_parse_rowmark(root->parse, prm->prti);
+ }
+
if (rc)
{
/*
! * Relation or parent relation is specified as a FOR UPDATE/SHARE
! * target, so handle that.
*
* For now, just ignore any [NO] KEY specification, since (a) it's
* not clear what that means for a remote table that we don't have

[1] http://www.postgresql.org/message-id/5487BB9D.7070605@lab.ntt.co.jp

Thanks,

Best regards,
Etsuro Fujita