-- Simple aggregates
explain (verbose, costs off)
select count(c6), sum(c1), avg(c1), min(c2), max(c1), stddev(c2), sum(c1) * (random() <= 1)::int as sum2 from ft1 where c2 < 5 group by c2 order by 1, 2;
- QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+------------------------------------------------------------------------------------------------------------------------------------------------------
Result
Output: (count(c6)), (sum(c1)), (avg(c1)), (min(c2)), (max(c1)), (stddev(c2)), ((sum(c1)) * ((random() <= '1'::double precision))::integer), c2
-> Sort
-> Foreign Scan
Output: (count(c6)), (sum(c1)), (avg(c1)), (min(c2)), (max(c1)), (stddev(c2)), c2
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT count(c6), sum("C 1"), avg("C 1"), min(c2), max("C 1"), stddev(c2), c2 FROM "S 1"."T 1" WHERE ((c2 < 5)) GROUP BY c2
+ Remote SQL: SELECT count(c6), sum("C 1"), avg("C 1"), min(c2), max("C 1"), stddev(c2), c2 FROM "S 1"."T 1" WHERE ((c2 < 5)) GROUP BY 7
(9 rows)
select count(c6), sum(c1), avg(c1), min(c2), max(c1), stddev(c2), sum(c1) * (random() <= 1)::int as sum2 from ft1 where c2 < 5 group by c2 order by 1, 2;
-- GROUP BY clause having expressions
explain (verbose, costs off)
select c2/2, sum(c2) * (c2/2) from ft1 group by c2/2 order by c2/2;
- QUERY PLAN
-------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------
Sort
Output: ((c2 / 2)), ((sum(c2) * (c2 / 2)))
Sort Key: ((ft1.c2 / 2))
-> Foreign Scan
Output: ((c2 / 2)), ((sum(c2) * (c2 / 2)))
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT (c2 / 2), (sum(c2) * (c2 / 2)) FROM "S 1"."T 1" GROUP BY ((c2 / 2))
+ Remote SQL: SELECT (c2 / 2), (sum(c2) * (c2 / 2)) FROM "S 1"."T 1" GROUP BY 1
(7 rows)
select c2/2, sum(c2) * (c2/2) from ft1 group by c2/2 order by c2/2;
-- Aggregates in subquery are pushed down.
explain (verbose, costs off)
select count(x.a), sum(x.a) from (select c2 a, sum(c1) b from ft1 group by c2, sqrt(c1) order by 1, 2) x;
- QUERY PLAN
-----------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------------
Aggregate
Output: count(ft1.c2), sum(ft1.c2)
-> Sort
-> Foreign Scan
Output: ft1.c2, (sum(ft1.c1)), (sqrt((ft1.c1)::double precision))
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT c2, sum("C 1"), sqrt("C 1") FROM "S 1"."T 1" GROUP BY c2, (sqrt("C 1"))
+ Remote SQL: SELECT c2, sum("C 1"), sqrt("C 1") FROM "S 1"."T 1" GROUP BY 1, 3
(9 rows)
select count(x.a), sum(x.a) from (select c2 a, sum(c1) b from ft1 group by c2, sqrt(c1) order by 1, 2) x;
-> Foreign Scan
Output: (c2 * ((random() <= '1'::double precision))::integer), ((sum(c1) * c2)), c2
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT (sum("C 1") * c2), c2 FROM "S 1"."T 1" GROUP BY c2
+ Remote SQL: SELECT (sum("C 1") * c2), c2 FROM "S 1"."T 1" GROUP BY 2
(7 rows)
select c2 * (random() <= 1)::int as sum1, sum(c1) * c2 as sum2 from ft1 group by c2 order by 1, 2;
-- GROUP BY clause in various forms, cardinal, alias and constant expression
explain (verbose, costs off)
select count(c2) w, c2 x, 5 y, 7.0 z from ft1 group by 2, y, 9.0::int order by 2;
- QUERY PLAN
-----------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------
Sort
Output: (count(c2)), c2, 5, 7.0, 9
Sort Key: ft1.c2
-> Foreign Scan
Output: (count(c2)), c2, 5, 7.0, 9
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT count(c2), c2, 5, 7.0, 9 FROM "S 1"."T 1" GROUP BY c2, 5::integer, 9::integer
+ Remote SQL: SELECT count(c2), c2, 5, 7.0, 9 FROM "S 1"."T 1" GROUP BY 2, 3, 5
(7 rows)
select count(c2) w, c2 x, 5 y, 7.0 z from ft1 group by 2, y, 9.0::int order by 2;
100 | 9 | 5 | 7.0
(10 rows)
+-- GROUP BY clause referring to same column multiple times
+-- Also, ORDER BY contains an aggregate function
+explain (verbose, costs off)
+select c2, c2 from ft1 where c2 > 6 group by 1, 2 order by sum(c1);
+ QUERY PLAN
+-----------------------------------------------------------------------------------------------
+ Sort
+ Output: c2, c2, (sum(c1))
+ Sort Key: (sum(ft1.c1))
+ -> Foreign Scan
+ Output: c2, c2, (sum(c1))
+ Relations: Aggregate on (public.ft1)
+ Remote SQL: SELECT c2, c2, sum("C 1") FROM "S 1"."T 1" WHERE ((c2 > 6)) GROUP BY 1, 2
+(7 rows)
+
+select c2, c2 from ft1 where c2 > 6 group by 1, 2 order by sum(c1);
+ c2 | c2
+----+----
+ 7 | 7
+ 8 | 8
+ 9 | 9
+(3 rows)
+
-- Testing HAVING clause shippability
explain (verbose, costs off)
select c2, sum(c1) from ft2 group by c2 having avg(c1) < 500 and sum(c1) < 49800 order by c2;
- QUERY PLAN
-----------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------------------------------------------------------
Sort
Output: c2, (sum(c1))
Sort Key: ft2.c2
-> Foreign Scan
Output: c2, (sum(c1))
Relations: Aggregate on (public.ft2)
- Remote SQL: SELECT c2, sum("C 1") FROM "S 1"."T 1" GROUP BY c2 HAVING ((avg("C 1") < 500::numeric)) AND ((sum("C 1") < 49800))
+ Remote SQL: SELECT c2, sum("C 1") FROM "S 1"."T 1" GROUP BY 1 HAVING ((avg("C 1") < 500::numeric)) AND ((sum("C 1") < 49800))
(7 rows)
select c2, sum(c1) from ft2 group by c2 having avg(c1) < 500 and sum(c1) < 49800 order by c2;
-- Unshippable HAVING clause will be evaluated locally, and other qual in HAVING clause is pushed down
explain (verbose, costs off)
select count(*) from (select c5, count(c1) from ft1 group by c5, sqrt(c2) having (avg(c1) / avg(c1)) * random() <= 1 and avg(c1) < 500) x;
- QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------------------------------------------------------
Aggregate
Output: count(*)
-> Foreign Scan
Output: ft1.c5, NULL::bigint, (sqrt((ft1.c2)::double precision))
Filter: (((((avg(ft1.c1)) / (avg(ft1.c1))))::double precision * random()) <= '1'::double precision)
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT c5, NULL::bigint, sqrt(c2), avg("C 1") FROM "S 1"."T 1" GROUP BY c5, (sqrt(c2)) HAVING ((avg("C 1") < 500::numeric))
+ Remote SQL: SELECT c5, NULL::bigint, sqrt(c2), avg("C 1") FROM "S 1"."T 1" GROUP BY 1, 3 HAVING ((avg("C 1") < 500::numeric))
(7 rows)
select count(*) from (select c5, count(c1) from ft1 group by c5, sqrt(c2) having (avg(c1) / avg(c1)) * random() <= 1 and avg(c1) < 500) x;
-- ORDER BY within aggregate, same column used to order
explain (verbose, costs off)
select array_agg(c1 order by c1) from ft1 where c1 < 100 group by c2 order by 1;
- QUERY PLAN
-----------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------------------------------------------------
Sort
Output: (array_agg(c1 ORDER BY c1)), c2
Sort Key: (array_agg(ft1.c1 ORDER BY ft1.c1))
-> Foreign Scan
Output: (array_agg(c1 ORDER BY c1)), c2
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT array_agg("C 1" ORDER BY "C 1" ASC NULLS LAST), c2 FROM "S 1"."T 1" WHERE (("C 1" < 100)) GROUP BY c2
+ Remote SQL: SELECT array_agg("C 1" ORDER BY "C 1" ASC NULLS LAST), c2 FROM "S 1"."T 1" WHERE (("C 1" < 100)) GROUP BY 2
(7 rows)
select array_agg(c1 order by c1) from ft1 where c1 < 100 group by c2 order by 1;
-- DISTINCT within aggregate
explain (verbose, costs off)
select array_agg(distinct (t1.c1)%5) from ft4 t1 full join ft5 t2 on (t1.c1 = t2.c1) where t1.c1 < 20 or (t1.c1 is null and t2.c1 < 5) group by (t2.c1)%3 order by 1;
- QUERY PLAN
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sort
Output: (array_agg(DISTINCT (t1.c1 % 5))), ((t2.c1 % 3))
Sort Key: (array_agg(DISTINCT (t1.c1 % 5)))
-> Foreign Scan
Output: (array_agg(DISTINCT (t1.c1 % 5))), ((t2.c1 % 3))
Relations: Aggregate on ((public.ft4 t1) FULL JOIN (public.ft5 t2))
- Remote SQL: SELECT array_agg(DISTINCT (r1.c1 % 5)), (r2.c1 % 3) FROM ("S 1"."T 3" r1 FULL JOIN "S 1"."T 4" r2 ON (((r1.c1 = r2.c1)))) WHERE (((r1.c1 < 20) OR ((r1.c1 IS NULL) AND (r2.c1 < 5)))) GROUP BY ((r2.c1 % 3))
+ Remote SQL: SELECT array_agg(DISTINCT (r1.c1 % 5)), (r2.c1 % 3) FROM ("S 1"."T 3" r1 FULL JOIN "S 1"."T 4" r2 ON (((r1.c1 = r2.c1)))) WHERE (((r1.c1 < 20) OR ((r1.c1 IS NULL) AND (r2.c1 < 5)))) GROUP BY 2
(7 rows)
select array_agg(distinct (t1.c1)%5) from ft4 t1 full join ft5 t2 on (t1.c1 = t2.c1) where t1.c1 < 20 or (t1.c1 is null and t2.c1 < 5) group by (t2.c1)%3 order by 1;
-- DISTINCT combined with ORDER BY within aggregate
explain (verbose, costs off)
select array_agg(distinct (t1.c1)%5 order by (t1.c1)%5) from ft4 t1 full join ft5 t2 on (t1.c1 = t2.c1) where t1.c1 < 20 or (t1.c1 is null and t2.c1 < 5) group by (t2.c1)%3 order by 1;
- QUERY PLAN
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sort
Output: (array_agg(DISTINCT (t1.c1 % 5) ORDER BY (t1.c1 % 5))), ((t2.c1 % 3))
Sort Key: (array_agg(DISTINCT (t1.c1 % 5) ORDER BY (t1.c1 % 5)))
-> Foreign Scan
Output: (array_agg(DISTINCT (t1.c1 % 5) ORDER BY (t1.c1 % 5))), ((t2.c1 % 3))
Relations: Aggregate on ((public.ft4 t1) FULL JOIN (public.ft5 t2))
- Remote SQL: SELECT array_agg(DISTINCT (r1.c1 % 5) ORDER BY ((r1.c1 % 5)) ASC NULLS LAST), (r2.c1 % 3) FROM ("S 1"."T 3" r1 FULL JOIN "S 1"."T 4" r2 ON (((r1.c1 = r2.c1)))) WHERE (((r1.c1 < 20) OR ((r1.c1 IS NULL) AND (r2.c1 < 5)))) GROUP BY ((r2.c1 % 3))
+ Remote SQL: SELECT array_agg(DISTINCT (r1.c1 % 5) ORDER BY ((r1.c1 % 5)) ASC NULLS LAST), (r2.c1 % 3) FROM ("S 1"."T 3" r1 FULL JOIN "S 1"."T 4" r2 ON (((r1.c1 = r2.c1)))) WHERE (((r1.c1 < 20) OR ((r1.c1 IS NULL) AND (r2.c1 < 5)))) GROUP BY 2
(7 rows)
select array_agg(distinct (t1.c1)%5 order by (t1.c1)%5) from ft4 t1 full join ft5 t2 on (t1.c1 = t2.c1) where t1.c1 < 20 or (t1.c1 is null and t2.c1 < 5) group by (t2.c1)%3 order by 1;
explain (verbose, costs off)
select array_agg(distinct (t1.c1)%5 order by (t1.c1)%5 desc nulls last) from ft4 t1 full join ft5 t2 on (t1.c1 = t2.c1) where t1.c1 < 20 or (t1.c1 is null and t2.c1 < 5) group by (t2.c1)%3 order by 1;
- QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sort
Output: (array_agg(DISTINCT (t1.c1 % 5) ORDER BY (t1.c1 % 5) DESC NULLS LAST)), ((t2.c1 % 3))
Sort Key: (array_agg(DISTINCT (t1.c1 % 5) ORDER BY (t1.c1 % 5) DESC NULLS LAST))
-> Foreign Scan
Output: (array_agg(DISTINCT (t1.c1 % 5) ORDER BY (t1.c1 % 5) DESC NULLS LAST)), ((t2.c1 % 3))
Relations: Aggregate on ((public.ft4 t1) FULL JOIN (public.ft5 t2))
- Remote SQL: SELECT array_agg(DISTINCT (r1.c1 % 5) ORDER BY ((r1.c1 % 5)) DESC NULLS LAST), (r2.c1 % 3) FROM ("S 1"."T 3" r1 FULL JOIN "S 1"."T 4" r2 ON (((r1.c1 = r2.c1)))) WHERE (((r1.c1 < 20) OR ((r1.c1 IS NULL) AND (r2.c1 < 5)))) GROUP BY ((r2.c1 % 3))
+ Remote SQL: SELECT array_agg(DISTINCT (r1.c1 % 5) ORDER BY ((r1.c1 % 5)) DESC NULLS LAST), (r2.c1 % 3) FROM ("S 1"."T 3" r1 FULL JOIN "S 1"."T 4" r2 ON (((r1.c1 = r2.c1)))) WHERE (((r1.c1 < 20) OR ((r1.c1 IS NULL) AND (r2.c1 < 5)))) GROUP BY 2
(7 rows)
select array_agg(distinct (t1.c1)%5 order by (t1.c1)%5 desc nulls last) from ft4 t1 full join ft5 t2 on (t1.c1 = t2.c1) where t1.c1 < 20 or (t1.c1 is null and t2.c1 < 5) group by (t2.c1)%3 order by 1;
-- FILTER within aggregate
explain (verbose, costs off)
select sum(c1) filter (where c1 < 100 and c2 > 5) from ft1 group by c2 order by 1 nulls last;
- QUERY PLAN
---------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+-------------------------------------------------------------------------------------------------------------------
Sort
Output: (sum(c1) FILTER (WHERE ((c1 < 100) AND (c2 > 5)))), c2
Sort Key: (sum(ft1.c1) FILTER (WHERE ((ft1.c1 < 100) AND (ft1.c2 > 5))))
-> Foreign Scan
Output: (sum(c1) FILTER (WHERE ((c1 < 100) AND (c2 > 5)))), c2
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT sum("C 1") FILTER (WHERE (("C 1" < 100) AND (c2 > 5))), c2 FROM "S 1"."T 1" GROUP BY c2
+ Remote SQL: SELECT sum("C 1") FILTER (WHERE (("C 1" < 100) AND (c2 > 5))), c2 FROM "S 1"."T 1" GROUP BY 2
(7 rows)
select sum(c1) filter (where c1 < 100 and c2 > 5) from ft1 group by c2 order by 1 nulls last;
-- DISTINCT, ORDER BY and FILTER within aggregate
explain (verbose, costs off)
select sum(c1%3), sum(distinct c1%3 order by c1%3) filter (where c1%3 < 2), c2 from ft1 where c2 = 6 group by c2;
- QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Foreign Scan
Output: (sum((c1 % 3))), (sum(DISTINCT (c1 % 3) ORDER BY (c1 % 3)) FILTER (WHERE ((c1 % 3) < 2))), c2
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT sum(("C 1" % 3)), sum(DISTINCT ("C 1" % 3) ORDER BY (("C 1" % 3)) ASC NULLS LAST) FILTER (WHERE (("C 1" % 3) < 2)), c2 FROM "S 1"."T 1" WHERE ((c2 = 6)) GROUP BY c2
+ Remote SQL: SELECT sum(("C 1" % 3)), sum(DISTINCT ("C 1" % 3) ORDER BY (("C 1" % 3)) ASC NULLS LAST) FILTER (WHERE (("C 1" % 3) < 2)), c2 FROM "S 1"."T 1" WHERE ((c2 = 6)) GROUP BY 3
(4 rows)
select sum(c1%3), sum(distinct c1%3 order by c1%3) filter (where c1%3 < 2), c2 from ft1 where c2 = 6 group by c2;
-- Ordered-sets within aggregate
explain (verbose, costs off)
select c2, rank('10'::varchar) within group (order by c6), percentile_cont(c2/10::numeric) within group (order by c1) from ft1 where c2 < 10 group by c2 having percentile_cont(c2/10::numeric) within group (order by c1) < 500 order by c2;
- QUERY PLAN
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sort
Output: c2, (rank('10'::character varying) WITHIN GROUP (ORDER BY c6)), (percentile_cont((((c2)::numeric / '10'::numeric))::double precision) WITHIN GROUP (ORDER BY ((c1)::double precision)))
Sort Key: ft1.c2
-> Foreign Scan
Output: c2, (rank('10'::character varying) WITHIN GROUP (ORDER BY c6)), (percentile_cont((((c2)::numeric / '10'::numeric))::double precision) WITHIN GROUP (ORDER BY ((c1)::double precision)))
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT c2, rank('10'::character varying) WITHIN GROUP (ORDER BY c6 ASC NULLS LAST), percentile_cont((c2 / 10::numeric)) WITHIN GROUP (ORDER BY ("C 1") ASC NULLS LAST) FROM "S 1"."T 1" WHERE ((c2 < 10)) GROUP BY c2 HAVING ((percentile_cont((c2 / 10::numeric)) WITHIN GROUP (ORDER BY ("C 1") ASC NULLS LAST) < 500::double precision))
+ Remote SQL: SELECT c2, rank('10'::character varying) WITHIN GROUP (ORDER BY c6 ASC NULLS LAST), percentile_cont((c2 / 10::numeric)) WITHIN GROUP (ORDER BY ("C 1") ASC NULLS LAST) FROM "S 1"."T 1" WHERE ((c2 < 10)) GROUP BY 1 HAVING ((percentile_cont((c2 / 10::numeric)) WITHIN GROUP (ORDER BY ("C 1") ASC NULLS LAST) < 500::double precision))
(7 rows)
select c2, rank('10'::varchar) within group (order by c6), percentile_cont(c2/10::numeric) within group (order by c1) from ft1 where c2 < 10 group by c2 having percentile_cont(c2/10::numeric) within group (order by c1) < 500 order by c2;
-- Using multiple arguments within aggregates
explain (verbose, costs off)
select c1, rank(c1, c2) within group (order by c1, c2) from ft1 group by c1, c2 having c1 = 6 order by 1;
- QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------
Foreign Scan
Output: c1, (rank(c1, c2) WITHIN GROUP (ORDER BY c1, c2)), c2
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT "C 1", rank("C 1", c2) WITHIN GROUP (ORDER BY "C 1" ASC NULLS LAST, c2 ASC NULLS LAST), c2 FROM "S 1"."T 1" WHERE (("C 1" = 6)) GROUP BY "C 1", c2
+ Remote SQL: SELECT "C 1", rank("C 1", c2) WITHIN GROUP (ORDER BY "C 1" ASC NULLS LAST, c2 ASC NULLS LAST), c2 FROM "S 1"."T 1" WHERE (("C 1" = 6)) GROUP BY 1, 3
(4 rows)
select c1, rank(c1, c2) within group (order by c1, c2) from ft1 group by c1, c2 having c1 = 6 order by 1;
-- Now aggregate will be pushed. Aggregate will display VARIADIC argument.
explain (verbose, costs off)
select c2, least_agg(c1) from ft1 where c2 < 100 group by c2 order by c2;
- QUERY PLAN
-------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+-----------------------------------------------------------------------------------------------------------------------
Sort
Output: c2, (least_agg(VARIADIC ARRAY[c1]))
Sort Key: ft1.c2
-> Foreign Scan
Output: c2, (least_agg(VARIADIC ARRAY[c1]))
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT c2, public.least_agg(VARIADIC ARRAY["C 1"]) FROM "S 1"."T 1" WHERE ((c2 < 100)) GROUP BY c2
+ Remote SQL: SELECT c2, public.least_agg(VARIADIC ARRAY["C 1"]) FROM "S 1"."T 1" WHERE ((c2 < 100)) GROUP BY 1
(7 rows)
select c2, least_agg(c1) from ft1 where c2 < 100 group by c2 order by c2;
-- Now this will be pushed as sort operator is part of the extension.
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;
- QUERY PLAN
------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+----------------------------------------------------------------------------------------------------------------------------------------------------------------
Foreign Scan
Output: (array_agg(c1 ORDER BY c1 USING <^ NULLS LAST)), c2
Relations: Aggregate on (public.ft2)
- Remote SQL: SELECT array_agg("C 1" ORDER BY "C 1" USING OPERATOR(public.<^) NULLS LAST), c2 FROM "S 1"."T 1" WHERE (("C 1" < 100)) AND ((c2 = 6)) GROUP BY c2
+ Remote SQL: SELECT array_agg("C 1" ORDER BY "C 1" USING OPERATOR(public.<^) NULLS LAST), c2 FROM "S 1"."T 1" WHERE (("C 1" < 100)) AND ((c2 = 6)) GROUP BY 2
(4 rows)
select array_agg(c1 order by c1 using operator(public.<^)) from ft2 where c2 = 6 and c1 < 100 group by c2;
-- Subquery in FROM clause having aggregate
explain (verbose, costs off)
select count(*), x.b from ft1, (select c2 a, sum(c1) b from ft1 group by c2) x where ft1.c2 = x.a group by x.b order by 1, 2;
- QUERY PLAN
-------------------------------------------------------------------------------------------------
+ QUERY PLAN
+-----------------------------------------------------------------------------------------------
Sort
Output: (count(*)), x.b
Sort Key: (count(*)), x.b
-> Foreign Scan
Output: ft1_1.c2, (sum(ft1_1.c1))
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT c2, sum("C 1") FROM "S 1"."T 1" GROUP BY c2
+ Remote SQL: SELECT c2, sum("C 1") FROM "S 1"."T 1" GROUP BY 1
(21 rows)
select count(*), x.b from ft1, (select c2 a, sum(c1) b from ft1 group by c2) x where ft1.c2 = x.a group by x.b order by 1, 2;
-- FULL join with IS NULL check in HAVING
explain (verbose, costs off)
select avg(t1.c1), sum(t2.c1) from ft4 t1 full join ft5 t2 on (t1.c1 = t2.c1) group by t2.c1 having (avg(t1.c1) is null and sum(t2.c1) < 10) or sum(t2.c1) is null order by 1 nulls last, 2;
- QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sort
Output: (avg(t1.c1)), (sum(t2.c1)), t2.c1
Sort Key: (avg(t1.c1)), (sum(t2.c1))
-> Foreign Scan
Output: (avg(t1.c1)), (sum(t2.c1)), t2.c1
Relations: Aggregate on ((public.ft4 t1) FULL JOIN (public.ft5 t2))
- Remote SQL: SELECT avg(r1.c1), sum(r2.c1), r2.c1 FROM ("S 1"."T 3" r1 FULL JOIN "S 1"."T 4" r2 ON (((r1.c1 = r2.c1)))) GROUP BY r2.c1 HAVING ((((avg(r1.c1) IS NULL) AND (sum(r2.c1) < 10)) OR (sum(r2.c1) IS NULL)))
+ Remote SQL: SELECT avg(r1.c1), sum(r2.c1), r2.c1 FROM ("S 1"."T 3" r1 FULL JOIN "S 1"."T 4" r2 ON (((r1.c1 = r2.c1)))) GROUP BY 3 HAVING ((((avg(r1.c1) IS NULL) AND (sum(r2.c1) < 10)) OR (sum(r2.c1) IS NULL)))
(7 rows)
select avg(t1.c1), sum(t2.c1) from ft4 t1 full join ft5 t2 on (t1.c1 = t2.c1) group by t2.c1 having (avg(t1.c1) is null and sum(t2.c1) < 10) or sum(t2.c1) is null order by 1 nulls last, 2;
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 < 3 and t1."C 1" < 100 order by 1;
- QUERY PLAN
-----------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+------------------------------------------------------------------------------------------------------
Sort
Output: t1.c2, qry.sum
Sort Key: t1.c2
-> Foreign Scan
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"
+ Remote SQL: SELECT sum(("C 1" + $1::integer)), "C 1" FROM "S 1"."T 1" GROUP BY 2
(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 < 3 and t1."C 1" < 100 order by 1;
-- DISTINCT itself is not pushed down, whereas underneath aggregate is pushed
explain (verbose, costs off)
select distinct sum(c1)/1000 s from ft2 where c2 < 6 group by c2 order by 1;
- QUERY PLAN
---------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+-------------------------------------------------------------------------------------------------------
Unique
Output: ((sum(c1) / 1000)), c2
-> Sort
-> Foreign Scan
Output: ((sum(c1) / 1000)), c2
Relations: Aggregate on (public.ft2)
- Remote SQL: SELECT (sum("C 1") / 1000), c2 FROM "S 1"."T 1" WHERE ((c2 < 6)) GROUP BY c2
+ Remote SQL: SELECT (sum("C 1") / 1000), c2 FROM "S 1"."T 1" WHERE ((c2 < 6)) GROUP BY 2
(9 rows)
select distinct sum(c1)/1000 s from ft2 where c2 < 6 group by c2 order by 1;
-- WindowAgg
explain (verbose, costs off)
select c2, sum(c2), count(c2) over (partition by c2%2) from ft2 where c2 < 10 group by c2 order by 1;
- QUERY PLAN
--------------------------------------------------------------------------------------------------------------
+ QUERY PLAN
+------------------------------------------------------------------------------------------------------------
Sort
Output: c2, (sum(c2)), (count(c2) OVER (?)), ((c2 % 2))
Sort Key: ft2.c2
-> Foreign Scan
Output: c2, ((c2 % 2)), (sum(c2))
Relations: Aggregate on (public.ft2)
- Remote SQL: SELECT c2, (c2 % 2), sum(c2) FROM "S 1"."T 1" WHERE ((c2 < 10)) GROUP BY c2
+ Remote SQL: SELECT c2, (c2 % 2), sum(c2) FROM "S 1"."T 1" WHERE ((c2 < 10)) GROUP BY 1
(12 rows)
select c2, sum(c2), count(c2) over (partition by c2%2) from ft2 where c2 < 10 group by c2 order by 1;
explain (verbose, costs off)
select c2, array_agg(c2) over (partition by c2%2 order by c2 desc) from ft1 where c2 < 10 group by c2 order by 1;
- QUERY PLAN
-----------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------------------
Sort
Output: c2, (array_agg(c2) OVER (?)), ((c2 % 2))
Sort Key: ft1.c2
-> Foreign Scan
Output: c2, ((c2 % 2))
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT c2, (c2 % 2) FROM "S 1"."T 1" WHERE ((c2 < 10)) GROUP BY c2
+ Remote SQL: SELECT c2, (c2 % 2) FROM "S 1"."T 1" WHERE ((c2 < 10)) GROUP BY 1
(12 rows)
select c2, array_agg(c2) over (partition by c2%2 order by c2 desc) from ft1 where c2 < 10 group by c2 order by 1;
explain (verbose, costs off)
select c2, array_agg(c2) over (partition by c2%2 order by c2 range between current row and unbounded following) from ft1 where c2 < 10 group by c2 order by 1;
- QUERY PLAN
-----------------------------------------------------------------------------------------------------
+ QUERY PLAN
+---------------------------------------------------------------------------------------------------
Sort
Output: c2, (array_agg(c2) OVER (?)), ((c2 % 2))
Sort Key: ft1.c2
-> Foreign Scan
Output: c2, ((c2 % 2))
Relations: Aggregate on (public.ft1)
- Remote SQL: SELECT c2, (c2 % 2) FROM "S 1"."T 1" WHERE ((c2 < 10)) GROUP BY c2
+ Remote SQL: SELECT c2, (c2 % 2) FROM "S 1"."T 1" WHERE ((c2 < 10)) GROUP BY 1
(12 rows)
select c2, array_agg(c2) over (partition by c2%2 order by c2 range between current row and unbounded following) from ft1 where c2 < 10 group by c2 order by 1;
foreign_grouping_ok(PlannerInfo *root, RelOptInfo *grouped_rel)
{
Query *query = root->parse;
- PathTarget *grouping_target;
+ PathTarget *grouping_target = root->upper_targets[UPPERREL_GROUP_AGG];
PgFdwRelationInfo *fpinfo = (PgFdwRelationInfo *) grouped_rel->fdw_private;
PgFdwRelationInfo *ofpinfo;
List *aggvars;
int i;
List *tlist = NIL;
- /* Grouping Sets are not pushable */
+ /* We currently don't support pushing Grouping Sets. */
if (query->groupingSets)
return false;
ofpinfo = (PgFdwRelationInfo *) fpinfo->outerrel->fdw_private;
/*
- * If underneath input relation has any local conditions, those conditions
+ * If underlying scan relation has any local conditions, those conditions
* are required to be applied before performing aggregation. Hence the
* aggregate cannot be pushed down.
*/
return false;
/*
- * The targetlist expected from this node and the targetlist pushed down
- * to the foreign server may be different. The latter requires
- * sortgrouprefs to be set to push down GROUP BY clause, but should not
- * have those arising from ORDER BY clause. These sortgrouprefs may be
- * different from those in the plan's targetlist. Use a copy of path
- * target to record the new sortgrouprefs.
- */
- grouping_target = copy_pathtarget(root->upper_targets[UPPERREL_GROUP_AGG]);
-
- /*
- * Evaluate grouping targets and check whether they are safe to push down
- * to the foreign side. All GROUP BY expressions will be part of the
- * grouping target and thus there is no need to evaluate it separately.
- * While doing so, add required expressions into target list which can
- * then be used to pass to foreign server.
+ * Examine grouping expressions, as well as other expressions we'd need to
+ * compute, and check whether they are safe to push down to the foreign
+ * server. All GROUP BY expressions will be part of the grouping target
+ * and thus there is no need to search for them separately. Add grouping
+ * expressions into target list which will be passed to foreign server.
*/
i = 0;
foreach(lc, grouping_target->exprs)
/* Check whether this expression is part of GROUP BY clause */
if (sgref && get_sortgroupref_clause_noerr(sgref, query->groupClause))
{
+ TargetEntry *tle;
+
/*
- * If any of the GROUP BY expression is not shippable we can not
+ * If any GROUP BY expression is not shippable, then we cannot
* push down aggregation to the foreign server.
*/
if (!is_foreign_expr(root, grouped_rel, expr))
return false;
- /* Pushable, add to tlist */
- tlist = add_to_flat_tlist(tlist, list_make1(expr));
+ /*
+ * Pushable, so add to tlist. We need to create a TLE for this
+ * expression and apply the sortgroupref to it. We cannot use
+ * add_to_flat_tlist() here because that avoids making duplicate
+ * entries in the tlist. If there are duplicate entries with
+ * distinct sortgrouprefs, we have to duplicate that situation in
+ * the output tlist.
+ */
+ tle = makeTargetEntry(expr, list_length(tlist) + 1, NULL, false);
+ tle->ressortgroupref = sgref;
+ tlist = lappend(tlist, tle);
}
else
{
- /* Check entire expression whether it is pushable or not */
+ /*
+ * Non-grouping expression we need to compute. Is it shippable?
+ */
if (is_foreign_expr(root, grouped_rel, expr))
{
- /* Pushable, add to tlist */
+ /* Yes, so add to tlist as-is; OK to suppress duplicates */
tlist = add_to_flat_tlist(tlist, list_make1(expr));
}
else
{
- /*
- * If we have sortgroupref set, then it means that we have an
- * ORDER BY entry pointing to this expression. Since we are
- * not pushing ORDER BY with GROUP BY, clear it.
- */
- if (sgref)
- grouping_target->sortgrouprefs[i] = 0;
-
- /* Not matched exactly, pull the var with aggregates then */
+ /* Not pushable as a whole; extract its Vars and aggregates */
aggvars = pull_var_clause((Node *) expr,
PVC_INCLUDE_AGGREGATES);
+ /*
+ * If any aggregate expression is not shippable, then we
+ * cannot push down aggregation to the foreign server.
+ */
if (!is_foreign_expr(root, grouped_rel, (Expr *) aggvars))
return false;
/*
- * Add aggregates, if any, into the targetlist. Plain var
- * nodes should be either same as some GROUP BY expression or
- * part of some GROUP BY expression. In later case, the query
- * cannot refer plain var nodes without the surrounding
- * expression. In both the cases, they are already part of
+ * Add aggregates, if any, into the targetlist. Plain Vars
+ * outside an aggregate can be ignored, because they should be
+ * either same as some GROUP BY column or part of some GROUP
+ * BY expression. In either case, they are already part of
* the targetlist and thus no need to add them again. In fact
- * adding pulled plain var nodes in SELECT clause will cause
- * an error on the foreign server if they are not same as some
- * GROUP BY expression.
+ * including plain Vars in the tlist when they do not match a
+ * GROUP BY column would cause the foreign server to complain
+ * that the shipped query is invalid.
*/
foreach(l, aggvars)
{
}
/*
- * Classify the pushable and non-pushable having clauses and save them in
+ * Classify the pushable and non-pushable HAVING clauses and save them in
* remote_conds and local_conds of the grouped rel's fpinfo.
*/
if (root->hasHavingQual && query->havingQual)
}
}
- /* Transfer any sortgroupref data to the replacement tlist */
- apply_pathtarget_labeling_to_tlist(tlist, grouping_target);
-
/* Store generated targetlist */
fpinfo->grouped_tlist = tlist;
projects / postgresql / commitdiff