postgres-fdw-aggregate-pushdown-costsize-1.patch

*** a/contrib/postgres_fdw/expected/postgres_fdw.out
--- b/contrib/postgres_fdw/expected/postgres_fdw.out
***************
*** 3209,3214 **** select array_agg(c1 order by c1 using operator(public.<^)) from ft2 where c2 = 6
--- 3209,3216 ----
           Remote SQL: SELECT "C 1", c2 FROM "S 1"."T 1" WHERE (("C 1" < 100)) AND ((c2 = 6))
  (6 rows)
  
+ -- Update local stats on ft2
+ ANALYZE ft2;
  -- Add into extension
  alter extension postgres_fdw add operator class my_op_class using btree;
  alter extension postgres_fdw add function my_op_cmp(a int, b int);
*** a/contrib/postgres_fdw/postgres_fdw.c
--- b/contrib/postgres_fdw/postgres_fdw.c
***************
*** 5496,5501 **** add_foreign_grouping_paths(PlannerInfo *root, RelOptInfo *input_rel,
--- 5496,5514 ----
  	if (!foreign_grouping_ok(root, grouped_rel, extra->havingQual))
  		return;
  
+ 	/*
+ 	 * Compute the selectivity and cost of the local_conds, so we don't have
+ 	 * to do it over again for each path.  The best we can do for these
+ 	 * conditions is to estimate selectivity on the basis of local statistics.
+ 	 */
+ 	fpinfo->local_conds_sel = clauselist_selectivity(root,
+ 													 fpinfo->local_conds,
+ 													 0,
+ 													 JOIN_INNER,
+ 													 NULL);
+ 
+ 	cost_qual_eval(&fpinfo->local_conds_cost, fpinfo->local_conds, root);
+ 
  	/* Estimate the cost of push down */
  	estimate_path_cost_size(root, grouped_rel, NIL, NIL, &rows,
  							&width, &startup_cost, &total_cost);
*** a/contrib/postgres_fdw/sql/postgres_fdw.sql
--- b/contrib/postgres_fdw/sql/postgres_fdw.sql
***************
*** 807,812 **** create operator class my_op_class for type int using btree family my_op_family a
--- 807,815 ----
  explain (verbose, costs off)
  select array_agg(c1 order by c1 using operator(public.<^)) from ft2 where c2 = 6 and c1 < 100 group by c2;
  
+ -- Update local stats on ft2
+ ANALYZE ft2;
+ 
  -- Add into extension
  alter extension postgres_fdw add operator class my_op_class using btree;
  alter extension postgres_fdw add function my_op_cmp(a int, b int);