From aa7f593b1ffa9717bd5570174944c06c482d1c1f Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Wed, 25 Jan 2017 08:31:31 -0500
Subject: [PATCH] Improve speed of contrib/postgres_fdw regression tests.
Commit 7012b132d added some tests that consumed an excessive amount of
time, more than tripling the time needed for "make installcheck" for this
module. Add filter conditions to reduce the number of rows scanned,
bringing the runtime down to within hailing distance of what it was before.
Jeevan Chalke and Ashutosh Bapat, per a gripe from me
Discussion: https://postgr.es/m/16565.1478104765@sss.pgh.pa.us
---
.../postgres_fdw/expected/postgres_fdw.out | 36 ++++++++-----------
contrib/postgres_fdw/sql/postgres_fdw.sql | 12 +++----
2 files changed, 21 insertions(+), 27 deletions(-)
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 0045f3fef8d..3a092804a2d 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -2685,9 +2685,9 @@ select sum(c1%3), sum(distinct c1%3 order by c1%3) filter (where c1%3 < 2), c2 f
-- Outer query is aggregation query
explain (verbose, costs off)
-select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 order by 1;
- QUERY PLAN
--------------------------------------------------------------------------------------------------------
+select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 where t2.c2 % 6 = 0 order by 1;
+ QUERY PLAN
+------------------------------------------------------------------------------------------------------------------------------
Unique
Output: ((SubPlan 1))
-> Sort
@@ -2696,14 +2696,14 @@ select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft
-> Foreign Scan
Output: (SubPlan 1)
Relations: Aggregate on (public.ft2 t2)
- Remote SQL: SELECT count(*) FILTER (WHERE ((c2 = 6) AND ("C 1" < 10))) FROM "S 1"."T 1"
+ Remote SQL: SELECT count(*) FILTER (WHERE ((c2 = 6) AND ("C 1" < 10))) FROM "S 1"."T 1" WHERE (((c2 % 6) = 0))
SubPlan 1
-> Foreign Scan on public.ft1 t1
Output: (count(*) FILTER (WHERE ((t2.c2 = 6) AND (t2.c1 < 10))))
Remote SQL: SELECT NULL FROM "S 1"."T 1" WHERE (("C 1" = 6))
(13 rows)
-select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 order by 1;
+select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 where t2.c2 % 6 = 0 order by 1;
count
-------
1
@@ -2711,7 +2711,7 @@ select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft
-- Inner query is aggregation query
explain (verbose, costs off)
-select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 order by 1;
+select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 where t2.c2 % 6 = 0 order by 1;
QUERY PLAN
------------------------------------------------------------------------------------------------------------------------------------------------------
Unique
@@ -2721,7 +2721,7 @@ select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) fro
Sort Key: ((SubPlan 1))
-> Foreign Scan on public.ft2 t2
Output: (SubPlan 1)
- Remote SQL: SELECT "C 1", c2 FROM "S 1"."T 1"
+ Remote SQL: SELECT "C 1", c2 FROM "S 1"."T 1" WHERE (((c2 % 6) = 0))
SubPlan 1
-> Foreign Scan
Output: (count(t1.c1) FILTER (WHERE ((t2.c2 = 6) AND (t2.c1 < 10))))
@@ -2729,7 +2729,7 @@ select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) fro
Remote SQL: SELECT count("C 1") FILTER (WHERE (($1::integer = 6) AND ($2::integer < 10))) FROM "S 1"."T 1" WHERE (("C 1" = 6))
(13 rows)
-select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 order by 1;
+select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 where t2.c2 % 6 = 0 order by 1;
count
-------
0
@@ -3086,7 +3086,7 @@ select sum(c2) * (random() <= 1)::int as sum from ft1 order by 1;
-- LATERAL join, with parameterization
set enable_hashagg to false;
explain (verbose, costs off)
-select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum from ft2 t2 group by t2.c1) qry where t1.c2 * 2 = qry.sum and t1.c2 < 10 order by 1;
+select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum from ft2 t2 group by t2.c1) qry where t1.c2 * 2 = qry.sum and t1.c2 < 3 and t1."C 1" < 100 order by 1;
QUERY PLAN
----------------------------------------------------------------------------------------------------------
Sort
@@ -3094,9 +3094,10 @@ select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum fr
Sort Key: t1.c2
-> Nested Loop
Output: t1.c2, qry.sum
- -> Seq Scan on "S 1"."T 1" t1
+ -> Index Scan using t1_pkey on "S 1"."T 1" t1
Output: t1."C 1", t1.c2, t1.c3, t1.c4, t1.c5, t1.c6, t1.c7, t1.c8
- Filter: (t1.c2 < 10)
+ Index Cond: (t1."C 1" < 100)
+ Filter: (t1.c2 < 3)
-> Subquery Scan on qry
Output: qry.sum, t2.c1
Filter: ((t1.c2 * 2) = qry.sum)
@@ -3104,21 +3105,14 @@ select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum fr
Output: (sum((t2.c1 + t1."C 1"))), t2.c1
Relations: Aggregate on (public.ft2 t2)
Remote SQL: SELECT sum(("C 1" + $1::integer)), "C 1" FROM "S 1"."T 1" GROUP BY "C 1"
-(15 rows)
+(16 rows)
-select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum from ft2 t2 group by t2.c1) qry where t1.c2 * 2 = qry.sum and t1.c2 < 10 order by 1;
+select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum from ft2 t2 group by t2.c1) qry where t1.c2 * 2 = qry.sum and t1.c2 < 3 and t1."C 1" < 100 order by 1;
c2 | sum
----+-----
1 | 2
2 | 4
- 3 | 6
- 4 | 8
- 5 | 10
- 6 | 12
- 7 | 14
- 8 | 16
- 9 | 18
-(9 rows)
+(2 rows)
reset enable_hashagg;
-- Check with placeHolderVars
diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index 919177649ed..e19a3ef398c 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -641,12 +641,12 @@ select sum(c1%3), sum(distinct c1%3 order by c1%3) filter (where c1%3 < 2), c2 f
-- Outer query is aggregation query
explain (verbose, costs off)
-select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 order by 1;
-select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 order by 1;
+select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 where t2.c2 % 6 = 0 order by 1;
+select distinct (select count(*) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 where t2.c2 % 6 = 0 order by 1;
-- Inner query is aggregation query
explain (verbose, costs off)
-select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 order by 1;
-select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 order by 1;
+select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 where t2.c2 % 6 = 0 order by 1;
+select distinct (select count(t1.c1) filter (where t2.c2 = 6 and t2.c1 < 10) from ft1 t1 where t1.c1 = 6) from ft2 t2 where t2.c2 % 6 = 0 order by 1;
-- Aggregate not pushed down as FILTER condition is not pushable
explain (verbose, costs off)
@@ -802,8 +802,8 @@ select sum(c2) * (random() <= 1)::int as sum from ft1 order by 1;
-- LATERAL join, with parameterization
set enable_hashagg to false;
explain (verbose, costs off)
-select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum from ft2 t2 group by t2.c1) qry where t1.c2 * 2 = qry.sum and t1.c2 < 10 order by 1;
-select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum from ft2 t2 group by t2.c1) qry where t1.c2 * 2 = qry.sum and t1.c2 < 10 order by 1;
+select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum from ft2 t2 group by t2.c1) qry where t1.c2 * 2 = qry.sum and t1.c2 < 3 and t1."C 1" < 100 order by 1;
+select c2, sum from "S 1"."T 1" t1, lateral (select sum(t2.c1 + t1."C 1") sum from ft2 t2 group by t2.c1) qry where t1.c2 * 2 = qry.sum and t1.c2 < 3 and t1."C 1" < 100 order by 1;
reset enable_hashagg;
-- Check with placeHolderVars
--
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