postgres_fdw: Rephrase comment.

Per gripe from Thomas Munro, who only complained about a more
localized problem, but I couldn't resist a bit more wordsmithing.

diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 4b6ec14c65b795725518d4eb3fa2dfe5accfa343..ccfad1b82a3a8d1fb15e031f255104f29243a77b 100644 (file)
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -4264,16 +4264,15 @@ postgresGetForeignJoinPaths(PlannerInfo *root,
    fpinfo->attrs_used = NULL;
 
    /*
-    * In case there is a possibility that EvalPlanQual will be executed, we
-    * should be able to reconstruct the row, from base relations applying all
-    * the conditions. We create a local plan from a suitable local path
-    * available in the path list. In case such a path doesn't exist, we can
-    * not push the join to the foreign server since we won't be able to
+    * If there is a possibility that EvalPlanQual will be executed, we need
+    * to be able to reconstruct the row using scans of the base relations.
+    * GetExistingLocalJoinPath will find a suitable path for this purpose in
+    * the path list of the joinrel, if one exists.  We must be careful to
+    * call it before adding any ForeignPath, since the ForeignPath might
+    * dominate the only suitable local path available.  We also do it before
     * reconstruct the row for EvalPlanQual(). Find an alternative local path
-    * before we add ForeignPath, lest the new path would kick possibly the
-    * only local path. Do this before calling foreign_join_ok(), since that
-    * function updates fpinfo and marks it as pushable if the join is found
-    * to be pushable.
+    * calling foreign_join_ok(), since that function updates fpinfo and marks
+    * it as pushable if the join is found to be pushable.
     */
    if (root->parse->commandType == CMD_DELETE ||
        root->parse->commandType == CMD_UPDATE ||