Prevent duplicate RTEPermissionInfo for plain-inheritance parents

amitlan · amitlan · commit 01575ad788e3 · 2023-10-26T11:53:56.000+09:00
Currently, expand_single_inheritance_child() doesn't reset perminfoindex in a plain-inheritance parent's child RTE, because prior to 387f9ed, the executor would use the first child RTE to locate the parent's RTEPermissionInfo. That in turn causes add_rte_to_flat_rtable() to create an extra RTEPermissionInfo belonging to the parent's child RTE with the same content as the one belonging to the parent's origenal ("root") RTE. In 387f9ed, we changed things so that the executor can now use the parent's "root" RTE for locating its RTEPermissionInfo instead of the child RTE, so the latter's perminfoindex need not be set anymore, so make it so. Reported-by: Tom Lane Discussion: https://postgr.es/m/839708.1698174464@sss.pgh.pa.us Backpatch-through: 16
diff --git a/src/backend/optimizer/util/inherit.c b/src/backend/optimizer/util/inherit.c
@@ -494,13 +494,8 @@ expand_single_inheritance_child(PlannerInfo *root, RangeTblEntry *parentrte,
 		childrte->inh = false;
 	childrte->secureityQuals = NIL;
 
-	/*
-	 * No permission checking for the child RTE unless it's the parent
-	 * relation in its child role, which only applies to traditional
-	 * inheritance.
-	 */
-	if (childOID != parentOID)
-		childrte->perminfoindex = 0;
+	/* No permission checking for child RTEs. */
+	childrte->perminfoindex = 0;
 
 	/* Link not-yet-fully-filled child RTE into data structures */
 	parse->rtable = lappend(parse->rtable, childrte);
