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citus/src/test/regress/expected/multi_router_planner.out

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ALTER SEQUENCE pg_catalog.pg_dist_shardid_seq RESTART 840000;
ALTER SEQUENCE pg_catalog.pg_dist_jobid_seq RESTART 840000;
-- ===================================================================
-- test router planner functionality for single shard select queries
-- ===================================================================
CREATE TABLE articles_hash (
id bigint NOT NULL,
author_id bigint NOT NULL,
title varchar(20) NOT NULL,
word_count integer
);
CREATE TABLE articles_range (
id bigint NOT NULL,
author_id bigint NOT NULL,
title varchar(20) NOT NULL,
word_count integer
);
-- Check for the existence of line 'DEBUG: Creating router plan'
-- to determine if router planner is used.
-- this table is used in a CTE test
CREATE TABLE authors_hash ( name text, id bigint );
-- this table is used in router executor tests
CREATE TABLE articles_single_shard_hash (LIKE articles_hash);
SELECT master_create_distributed_table('articles_hash', 'author_id', 'hash');
master_create_distributed_table
---------------------------------
(1 row)
SELECT master_create_distributed_table('articles_single_shard_hash', 'author_id', 'hash');
master_create_distributed_table
---------------------------------
(1 row)
-- test when a table is distributed but no shards created yet
SELECT count(*) from articles_hash;
count
-------
0
(1 row)
SELECT master_create_worker_shards('articles_hash', 2, 1);
master_create_worker_shards
-----------------------------
(1 row)
SELECT master_create_worker_shards('articles_single_shard_hash', 1, 1);
master_create_worker_shards
-----------------------------
(1 row)
-- create a bunch of test data
INSERT INTO articles_hash VALUES ( 1, 1, 'arsenous', 9572);
INSERT INTO articles_hash VALUES ( 2, 2, 'abducing', 13642);
INSERT INTO articles_hash VALUES ( 3, 3, 'asternal', 10480);
INSERT INTO articles_hash VALUES ( 4, 4, 'altdorfer', 14551);
INSERT INTO articles_hash VALUES ( 5, 5, 'aruru', 11389);
INSERT INTO articles_hash VALUES ( 6, 6, 'atlases', 15459);
INSERT INTO articles_hash VALUES ( 7, 7, 'aseptic', 12298);
INSERT INTO articles_hash VALUES ( 8, 8, 'agatized', 16368);
INSERT INTO articles_hash VALUES ( 9, 9, 'alligate', 438);
INSERT INTO articles_hash VALUES (10, 10, 'aggrandize', 17277);
INSERT INTO articles_hash VALUES (11, 1, 'alamo', 1347);
INSERT INTO articles_hash VALUES (12, 2, 'archiblast', 18185);
INSERT INTO articles_hash VALUES (13, 3, 'aseyev', 2255);
INSERT INTO articles_hash VALUES (14, 4, 'andesite', 19094);
INSERT INTO articles_hash VALUES (15, 5, 'adversa', 3164);
INSERT INTO articles_hash VALUES (16, 6, 'allonym', 2);
INSERT INTO articles_hash VALUES (17, 7, 'auriga', 4073);
INSERT INTO articles_hash VALUES (18, 8, 'assembly', 911);
INSERT INTO articles_hash VALUES (19, 9, 'aubergiste', 4981);
INSERT INTO articles_hash VALUES (20, 10, 'absentness', 1820);
INSERT INTO articles_hash VALUES (21, 1, 'arcading', 5890);
INSERT INTO articles_hash VALUES (22, 2, 'antipope', 2728);
INSERT INTO articles_hash VALUES (23, 3, 'abhorring', 6799);
INSERT INTO articles_hash VALUES (24, 4, 'audacious', 3637);
INSERT INTO articles_hash VALUES (25, 5, 'antehall', 7707);
INSERT INTO articles_hash VALUES (26, 6, 'abington', 4545);
INSERT INTO articles_hash VALUES (27, 7, 'arsenous', 8616);
INSERT INTO articles_hash VALUES (28, 8, 'aerophyte', 5454);
INSERT INTO articles_hash VALUES (29, 9, 'amateur', 9524);
INSERT INTO articles_hash VALUES (30, 10, 'andelee', 6363);
INSERT INTO articles_hash VALUES (31, 1, 'athwartships', 7271);
INSERT INTO articles_hash VALUES (32, 2, 'amazon', 11342);
INSERT INTO articles_hash VALUES (33, 3, 'autochrome', 8180);
INSERT INTO articles_hash VALUES (34, 4, 'amnestied', 12250);
INSERT INTO articles_hash VALUES (35, 5, 'aminate', 9089);
INSERT INTO articles_hash VALUES (36, 6, 'ablation', 13159);
INSERT INTO articles_hash VALUES (37, 7, 'archduchies', 9997);
INSERT INTO articles_hash VALUES (38, 8, 'anatine', 14067);
INSERT INTO articles_hash VALUES (39, 9, 'anchises', 10906);
INSERT INTO articles_hash VALUES (40, 10, 'attemper', 14976);
INSERT INTO articles_hash VALUES (41, 1, 'aznavour', 11814);
INSERT INTO articles_hash VALUES (42, 2, 'ausable', 15885);
INSERT INTO articles_hash VALUES (43, 3, 'affixal', 12723);
INSERT INTO articles_hash VALUES (44, 4, 'anteport', 16793);
INSERT INTO articles_hash VALUES (45, 5, 'afrasia', 864);
INSERT INTO articles_hash VALUES (46, 6, 'atlanta', 17702);
INSERT INTO articles_hash VALUES (47, 7, 'abeyance', 1772);
INSERT INTO articles_hash VALUES (48, 8, 'alkylic', 18610);
INSERT INTO articles_hash VALUES (49, 9, 'anyone', 2681);
INSERT INTO articles_hash VALUES (50, 10, 'anjanette', 19519);
SET citus.task_executor_type TO 'real-time';
SET citus.large_table_shard_count TO 2;
SET client_min_messages TO 'DEBUG2';
-- insert a single row for the test
INSERT INTO articles_single_shard_hash VALUES (50, 10, 'anjanette', 19519);
DEBUG: Creating router plan
DEBUG: Plan is router executable
-- single-shard tests
-- test simple select for a single row
SELECT * FROM articles_hash WHERE author_id = 10 AND id = 50;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-----------+------------
50 | 10 | anjanette | 19519
(1 row)
-- get all titles by a single author
SELECT title FROM articles_hash WHERE author_id = 10;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
title
------------
aggrandize
absentness
andelee
attemper
anjanette
(5 rows)
-- try ordering them by word count
SELECT title, word_count FROM articles_hash
WHERE author_id = 10
ORDER BY word_count DESC NULLS LAST;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
title | word_count
------------+------------
anjanette | 19519
aggrandize | 17277
attemper | 14976
andelee | 6363
absentness | 1820
(5 rows)
-- look at last two articles by an author
SELECT title, id FROM articles_hash
WHERE author_id = 5
ORDER BY id
LIMIT 2;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
title | id
---------+----
aruru | 5
adversa | 15
(2 rows)
-- find all articles by two authors in same shard
-- but plan is not router executable due to order by
SELECT title, author_id FROM articles_hash
WHERE author_id = 7 OR author_id = 8
ORDER BY author_id ASC, id;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
title | author_id
-------------+-----------
aseptic | 7
auriga | 7
arsenous | 7
archduchies | 7
abeyance | 7
agatized | 8
assembly | 8
aerophyte | 8
anatine | 8
alkylic | 8
(10 rows)
-- same query is router executable with no order by
SELECT title, author_id FROM articles_hash
WHERE author_id = 7 OR author_id = 8;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
title | author_id
-------------+-----------
aseptic | 7
agatized | 8
auriga | 7
assembly | 8
arsenous | 7
aerophyte | 8
archduchies | 7
anatine | 8
abeyance | 7
alkylic | 8
(10 rows)
-- add in some grouping expressions, still on same shard
-- having queries unsupported in Citus
SELECT author_id, sum(word_count) AS corpus_size FROM articles_hash
WHERE author_id = 1 OR author_id = 7 OR author_id = 8 OR author_id = 10
GROUP BY author_id
HAVING sum(word_count) > 1000
ORDER BY sum(word_count) DESC;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
author_id | corpus_size
-----------+-------------
10 | 59955
8 | 55410
7 | 36756
1 | 35894
(4 rows)
-- however having clause is supported if it goes to a single shard
SELECT author_id, sum(word_count) AS corpus_size FROM articles_hash
WHERE author_id = 1
GROUP BY author_id
HAVING sum(word_count) > 1000
ORDER BY sum(word_count) DESC;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
author_id | corpus_size
-----------+-------------
1 | 35894
(1 row)
-- query is a single shard query but can't do shard pruning,
-- not router-plannable due to <= and IN
SELECT * FROM articles_hash WHERE author_id <= 1;
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
SELECT * FROM articles_hash WHERE author_id IN (1, 3);
NOTICE: cannot use shard pruning with ANY/ALL (array expression)
HINT: Consider rewriting the expression with OR/AND clauses.
NOTICE: cannot use shard pruning with ANY/ALL (array expression)
HINT: Consider rewriting the expression with OR/AND clauses.
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
3 | 3 | asternal | 10480
11 | 1 | alamo | 1347
13 | 3 | aseyev | 2255
21 | 1 | arcading | 5890
23 | 3 | abhorring | 6799
31 | 1 | athwartships | 7271
33 | 3 | autochrome | 8180
41 | 1 | aznavour | 11814
43 | 3 | affixal | 12723
(10 rows)
-- queries with CTEs are supported
WITH first_author AS ( SELECT id FROM articles_hash WHERE author_id = 1)
SELECT * FROM first_author;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id
----
1
11
21
31
41
(5 rows)
-- queries with CTEs are supported even if CTE is not referenced inside query
WITH first_author AS ( SELECT id FROM articles_hash WHERE author_id = 1)
SELECT title FROM articles_hash WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
title
--------------
arsenous
alamo
arcading
athwartships
aznavour
(5 rows)
-- two CTE joins are supported if they go to the same worker
WITH id_author AS ( SELECT id, author_id FROM articles_hash WHERE author_id = 1),
id_title AS (SELECT id, title from articles_hash WHERE author_id = 1)
SELECT * FROM id_author, id_title WHERE id_author.id = id_title.id;
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | id | title
----+-----------+----+--------------
1 | 1 | 1 | arsenous
11 | 1 | 11 | alamo
21 | 1 | 21 | arcading
31 | 1 | 31 | athwartships
41 | 1 | 41 | aznavour
(5 rows)
WITH id_author AS ( SELECT id, author_id FROM articles_hash WHERE author_id = 1),
id_title AS (SELECT id, title from articles_hash WHERE author_id = 3)
SELECT * FROM id_author, id_title WHERE id_author.id = id_title.id;
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | id | title
----+-----------+----+-------
(0 rows)
-- CTE joins are not supported if table shards are at different workers
WITH id_author AS ( SELECT id, author_id FROM articles_hash WHERE author_id = 1),
id_title AS (SELECT id, title from articles_hash WHERE author_id = 2)
SELECT * FROM id_author, id_title WHERE id_author.id = id_title.id;
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840000
ERROR: cannot perform distributed planning on this query
DETAIL: Complex table expressions are currently unsupported
-- recursive CTEs are supported when filtered on partition column
CREATE TABLE company_employees (company_id int, employee_id int, manager_id int);
SELECT master_create_distributed_table('company_employees', 'company_id', 'hash');
master_create_distributed_table
---------------------------------
(1 row)
SELECT master_create_worker_shards('company_employees', 4, 1);
master_create_worker_shards
-----------------------------
(1 row)
INSERT INTO company_employees values(1, 1, 0);
DEBUG: Creating router plan
DEBUG: Plan is router executable
INSERT INTO company_employees values(1, 2, 1);
DEBUG: Creating router plan
DEBUG: Plan is router executable
INSERT INTO company_employees values(1, 3, 1);
DEBUG: Creating router plan
DEBUG: Plan is router executable
INSERT INTO company_employees values(1, 4, 2);
DEBUG: Creating router plan
DEBUG: Plan is router executable
INSERT INTO company_employees values(1, 5, 4);
DEBUG: Creating router plan
DEBUG: Plan is router executable
INSERT INTO company_employees values(3, 1, 0);
DEBUG: Creating router plan
DEBUG: Plan is router executable
INSERT INTO company_employees values(3, 15, 1);
DEBUG: Creating router plan
DEBUG: Plan is router executable
INSERT INTO company_employees values(3, 3, 1);
DEBUG: Creating router plan
DEBUG: Plan is router executable
-- find employees at top 2 level within company hierarchy
WITH RECURSIVE hierarchy as (
SELECT *, 1 AS level
FROM company_employees
WHERE company_id = 1 and manager_id = 0
UNION
SELECT ce.*, (h.level+1)
FROM hierarchy h JOIN company_employees ce
ON (h.employee_id = ce.manager_id AND
h.company_id = ce.company_id AND
ce.company_id = 1))
SELECT * FROM hierarchy WHERE LEVEL <= 2;
DEBUG: predicate pruning for shardId 840004
DEBUG: predicate pruning for shardId 840005
DEBUG: predicate pruning for shardId 840006
DEBUG: predicate pruning for shardId 840004
DEBUG: predicate pruning for shardId 840005
DEBUG: predicate pruning for shardId 840006
DEBUG: Creating router plan
DEBUG: Plan is router executable
company_id | employee_id | manager_id | level
------------+-------------+------------+-------
1 | 1 | 0 | 1
1 | 2 | 1 | 2
1 | 3 | 1 | 2
(3 rows)
-- query becomes not router plannble and gets rejected
-- if filter on company is dropped
WITH RECURSIVE hierarchy as (
SELECT *, 1 AS level
FROM company_employees
WHERE company_id = 1 and manager_id = 0
UNION
SELECT ce.*, (h.level+1)
FROM hierarchy h JOIN company_employees ce
ON (h.employee_id = ce.manager_id AND
h.company_id = ce.company_id))
SELECT * FROM hierarchy WHERE LEVEL <= 2;
DEBUG: predicate pruning for shardId 840004
DEBUG: predicate pruning for shardId 840005
DEBUG: predicate pruning for shardId 840006
ERROR: cannot perform distributed planning on this query
DETAIL: Complex table expressions are currently unsupported
-- logically wrong query, query involves different shards
-- from the same table
WITH RECURSIVE hierarchy as (
SELECT *, 1 AS level
FROM company_employees
WHERE company_id = 3 and manager_id = 0
UNION
SELECT ce.*, (h.level+1)
FROM hierarchy h JOIN company_employees ce
ON (h.employee_id = ce.manager_id AND
h.company_id = ce.company_id AND
ce.company_id = 2))
SELECT * FROM hierarchy WHERE LEVEL <= 2;
DEBUG: predicate pruning for shardId 840003
DEBUG: predicate pruning for shardId 840005
DEBUG: predicate pruning for shardId 840006
DEBUG: predicate pruning for shardId 840003
DEBUG: predicate pruning for shardId 840004
DEBUG: predicate pruning for shardId 840005
ERROR: cannot perform distributed planning on this query
DETAIL: Complex table expressions are currently unsupported
-- CTE with queries other than SELECT is not supported
WITH new_article AS (
INSERT INTO articles_hash VALUES (1, 1, 'arsenous', 9572) RETURNING *
)
SELECT * FROM new_article;
ERROR: cannot perform distributed planning for the given modification
DETAIL: Data-modifying statements are not supported in the WITH clauses of distributed queries.
-- Modifying statement in nested CTE case is covered by PostgreSQL itself
WITH new_article AS (
WITH nested_cte AS (
INSERT INTO articles_hash VALUES (1, 1, 'arsenous', 9572) RETURNING *
)
SELECT * FROM nested_cte
)
SELECT * FROM new_article;
ERROR: WITH clause containing a data-modifying statement must be at the top level
LINE 2: WITH nested_cte AS (
^
-- Modifying statement in a CTE in subquwey is also covered by PostgreSQL
SELECT * FROM (
WITH new_article AS (
INSERT INTO articles_hash VALUES (1, 1, 'arsenous', 9572) RETURNING *
)
SELECT * FROM new_article
) AS subquery_cte;
ERROR: WITH clause containing a data-modifying statement must be at the top level
LINE 2: WITH new_article AS (
^
-- grouping sets are supported on single shard
SELECT
id, substring(title, 2, 1) AS subtitle, count(*)
FROM articles_hash
WHERE author_id = 1 or author_id = 3
GROUP BY GROUPING SETS ((id),(subtitle));
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | subtitle | count
----+----------+-------
1 | | 1
3 | | 1
11 | | 1
13 | | 1
21 | | 1
23 | | 1
31 | | 1
33 | | 1
41 | | 1
43 | | 1
| b | 1
| f | 1
| l | 1
| r | 2
| s | 2
| t | 1
| u | 1
| z | 1
(18 rows)
-- grouping sets are not supported on multiple shards
SELECT
id, substring(title, 2, 1) AS subtitle, count(*)
FROM articles_hash
WHERE author_id = 1 or author_id = 2
GROUP BY GROUPING SETS ((id),(subtitle));
ERROR: cannot perform distributed planning on this query
DETAIL: Grouping sets, cube, and rollup is currently unsupported
-- queries which involve functions in FROM clause are supported if it goes to a single worker.
SELECT * FROM articles_hash, position('om' in 'Thomas') WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count | position
----+-----------+--------------+------------+----------
1 | 1 | arsenous | 9572 | 3
11 | 1 | alamo | 1347 | 3
21 | 1 | arcading | 5890 | 3
31 | 1 | athwartships | 7271 | 3
41 | 1 | aznavour | 11814 | 3
(5 rows)
SELECT * FROM articles_hash, position('om' in 'Thomas') WHERE author_id = 1 or author_id = 3;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count | position
----+-----------+--------------+------------+----------
1 | 1 | arsenous | 9572 | 3
3 | 3 | asternal | 10480 | 3
11 | 1 | alamo | 1347 | 3
13 | 3 | aseyev | 2255 | 3
21 | 1 | arcading | 5890 | 3
23 | 3 | abhorring | 6799 | 3
31 | 1 | athwartships | 7271 | 3
33 | 3 | autochrome | 8180 | 3
41 | 1 | aznavour | 11814 | 3
43 | 3 | affixal | 12723 | 3
(10 rows)
-- they are not supported if multiple workers are involved
SELECT * FROM articles_hash, position('om' in 'Thomas') WHERE author_id = 1 or author_id = 2;
ERROR: cannot perform distributed planning on this query
DETAIL: Complex table expressions are currently unsupported
-- subqueries are not supported in WHERE clause in Citus
SELECT * FROM articles_hash WHERE author_id IN (SELECT id FROM authors_hash WHERE name LIKE '%a');
ERROR: cannot plan queries that include both regular and partitioned relations
SELECT * FROM articles_hash WHERE author_id IN (SELECT author_id FROM articles_hash WHERE author_id = 1 or author_id = 3);
ERROR: cannot perform distributed planning on this query
DETAIL: Join types other than inner/outer joins are currently unsupported
SELECT * FROM articles_hash WHERE author_id = (SELECT 1);
ERROR: cannot perform distributed planning on this query
DETAIL: Subqueries other than in from-clause are currently unsupported
-- unless the query can be transformed into a join
SELECT * FROM articles_hash
WHERE author_id IN (SELECT author_id FROM articles_hash WHERE author_id = 2)
ORDER BY articles_hash.id;
DEBUG: predicate pruning for shardId 840000
DEBUG: predicate pruning for shardId 840000
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+------------+------------
2 | 2 | abducing | 13642
12 | 2 | archiblast | 18185
22 | 2 | antipope | 2728
32 | 2 | amazon | 11342
42 | 2 | ausable | 15885
(5 rows)
-- subqueries are supported in FROM clause but they are not router plannable
SELECT articles_hash.id,test.word_count
FROM articles_hash, (SELECT id, word_count FROM articles_hash) AS test WHERE test.id = articles_hash.id
ORDER BY articles_hash.id;
DEBUG: join prunable for task partitionId 0 and 1
DEBUG: join prunable for task partitionId 0 and 2
DEBUG: join prunable for task partitionId 0 and 3
DEBUG: join prunable for task partitionId 1 and 0
DEBUG: join prunable for task partitionId 1 and 2
DEBUG: join prunable for task partitionId 1 and 3
DEBUG: join prunable for task partitionId 2 and 0
DEBUG: join prunable for task partitionId 2 and 1
DEBUG: join prunable for task partitionId 2 and 3
DEBUG: join prunable for task partitionId 3 and 0
DEBUG: join prunable for task partitionId 3 and 1
DEBUG: join prunable for task partitionId 3 and 2
DEBUG: pruning merge fetch taskId 1
DETAIL: Creating dependency on merge taskId 5
DEBUG: pruning merge fetch taskId 2
DETAIL: Creating dependency on merge taskId 5
DEBUG: pruning merge fetch taskId 4
DETAIL: Creating dependency on merge taskId 8
DEBUG: pruning merge fetch taskId 5
DETAIL: Creating dependency on merge taskId 8
DEBUG: pruning merge fetch taskId 7
DETAIL: Creating dependency on merge taskId 11
DEBUG: pruning merge fetch taskId 8
DETAIL: Creating dependency on merge taskId 11
DEBUG: pruning merge fetch taskId 10
DETAIL: Creating dependency on merge taskId 14
DEBUG: pruning merge fetch taskId 11
DETAIL: Creating dependency on merge taskId 14
ERROR: cannot use real time executor with repartition jobs
HINT: Set citus.task_executor_type to "task-tracker".
SELECT articles_hash.id,test.word_count
FROM articles_hash, (SELECT id, word_count FROM articles_hash) AS test
WHERE test.id = articles_hash.id and articles_hash.author_id = 1
ORDER BY articles_hash.id;
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: join prunable for task partitionId 0 and 1
DEBUG: join prunable for task partitionId 0 and 2
DEBUG: join prunable for task partitionId 0 and 3
DEBUG: join prunable for task partitionId 1 and 0
DEBUG: join prunable for task partitionId 1 and 2
DEBUG: join prunable for task partitionId 1 and 3
DEBUG: join prunable for task partitionId 2 and 0
DEBUG: join prunable for task partitionId 2 and 1
DEBUG: join prunable for task partitionId 2 and 3
DEBUG: join prunable for task partitionId 3 and 0
DEBUG: join prunable for task partitionId 3 and 1
DEBUG: join prunable for task partitionId 3 and 2
DEBUG: pruning merge fetch taskId 1
DETAIL: Creating dependency on merge taskId 3
DEBUG: pruning merge fetch taskId 2
DETAIL: Creating dependency on merge taskId 5
DEBUG: pruning merge fetch taskId 4
DETAIL: Creating dependency on merge taskId 5
DEBUG: pruning merge fetch taskId 5
DETAIL: Creating dependency on merge taskId 8
DEBUG: pruning merge fetch taskId 7
DETAIL: Creating dependency on merge taskId 7
DEBUG: pruning merge fetch taskId 8
DETAIL: Creating dependency on merge taskId 11
DEBUG: pruning merge fetch taskId 10
DETAIL: Creating dependency on merge taskId 9
DEBUG: pruning merge fetch taskId 11
DETAIL: Creating dependency on merge taskId 14
ERROR: cannot use real time executor with repartition jobs
HINT: Set citus.task_executor_type to "task-tracker".
-- subqueries are not supported in SELECT clause
SELECT a.title AS name, (SELECT a2.id FROM articles_single_shard_hash a2 WHERE a.id = a2.id LIMIT 1)
AS special_price FROM articles_hash a;
ERROR: cannot perform distributed planning on this query
DETAIL: Subqueries other than in from-clause are currently unsupported
-- simple lookup query
SELECT *
FROM articles_hash
WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- below query hits a single shard, router plannable
SELECT *
FROM articles_hash
WHERE author_id = 1 OR author_id = 17;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- below query hits two shards, not router plannable + not router executable
-- handled by real-time executor
SELECT *
FROM articles_hash
WHERE author_id = 1 OR author_id = 18;
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- rename the output columns
SELECT id as article_id, word_count * id as random_value
FROM articles_hash
WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
article_id | random_value
------------+--------------
1 | 9572
11 | 14817
21 | 123690
31 | 225401
41 | 484374
(5 rows)
-- we can push down co-located joins to a single worker
SELECT a.author_id as first_author, b.word_count as second_word_count
FROM articles_hash a, articles_hash b
WHERE a.author_id = 10 and a.author_id = b.author_id
LIMIT 3;
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
first_author | second_word_count
--------------+-------------------
10 | 17277
10 | 1820
10 | 6363
(3 rows)
-- following join is router plannable since the same worker
-- has both shards
SELECT a.author_id as first_author, b.word_count as second_word_count
FROM articles_hash a, articles_single_shard_hash b
WHERE a.author_id = 10 and a.author_id = b.author_id
LIMIT 3;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
first_author | second_word_count
--------------+-------------------
10 | 19519
10 | 19519
10 | 19519
(3 rows)
-- following join is not router plannable since there are no
-- workers containing both shards, added a CTE to make this fail
-- at logical planner
WITH single_shard as (SELECT * FROM articles_single_shard_hash)
SELECT a.author_id as first_author, b.word_count as second_word_count
FROM articles_hash a, single_shard b
WHERE a.author_id = 2 and a.author_id = b.author_id
LIMIT 3;
DEBUG: predicate pruning for shardId 840000
DEBUG: Found no worker with all shard placements
ERROR: cannot perform distributed planning on this query
DETAIL: Complex table expressions are currently unsupported
-- single shard select with limit is router plannable
SELECT *
FROM articles_hash
WHERE author_id = 1
LIMIT 3;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+----------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
(3 rows)
-- single shard select with limit + offset is router plannable
SELECT *
FROM articles_hash
WHERE author_id = 1
LIMIT 2
OFFSET 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+----------+------------
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
(2 rows)
-- single shard select with limit + offset + order by is router plannable
SELECT *
FROM articles_hash
WHERE author_id = 1
ORDER BY id desc
LIMIT 2
OFFSET 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
31 | 1 | athwartships | 7271
21 | 1 | arcading | 5890
(2 rows)
-- single shard select with group by on non-partition column is router plannable
SELECT id
FROM articles_hash
WHERE author_id = 1
GROUP BY id
ORDER BY id;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id
----
1
11
21
31
41
(5 rows)
-- single shard select with distinct is router plannable
SELECT DISTINCT id
FROM articles_hash
WHERE author_id = 1
ORDER BY id;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id
----
1
11
21
31
41
(5 rows)
-- single shard aggregate is router plannable
SELECT avg(word_count)
FROM articles_hash
WHERE author_id = 2;
DEBUG: predicate pruning for shardId 840000
DEBUG: Creating router plan
DEBUG: Plan is router executable
avg
--------------------
12356.400000000000
(1 row)
-- max, min, sum, count are router plannable on single shard
SELECT max(word_count) as max, min(word_count) as min,
sum(word_count) as sum, count(word_count) as cnt
FROM articles_hash
WHERE author_id = 2;
DEBUG: predicate pruning for shardId 840000
DEBUG: Creating router plan
DEBUG: Plan is router executable
max | min | sum | cnt
-------+------+-------+-----
18185 | 2728 | 61782 | 5
(1 row)
-- queries with aggregates and group by supported on single shard
SELECT max(word_count)
FROM articles_hash
WHERE author_id = 1
GROUP BY author_id;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
max
-------
11814
(1 row)
-- router plannable union queries are supported
(SELECT * FROM articles_hash WHERE author_id = 1)
UNION
(SELECT * FROM articles_hash WHERE author_id = 3);
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
3 | 3 | asternal | 10480
43 | 3 | affixal | 12723
23 | 3 | abhorring | 6799
13 | 3 | aseyev | 2255
11 | 1 | alamo | 1347
41 | 1 | aznavour | 11814
1 | 1 | arsenous | 9572
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
33 | 3 | autochrome | 8180
(10 rows)
SELECT * FROM (
(SELECT * FROM articles_hash WHERE author_id = 1)
UNION
(SELECT * FROM articles_hash WHERE author_id = 3)) uu;
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
3 | 3 | asternal | 10480
43 | 3 | affixal | 12723
23 | 3 | abhorring | 6799
13 | 3 | aseyev | 2255
11 | 1 | alamo | 1347
41 | 1 | aznavour | 11814
1 | 1 | arsenous | 9572
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
33 | 3 | autochrome | 8180
(10 rows)
(SELECT LEFT(title, 1) FROM articles_hash WHERE author_id = 1)
UNION
(SELECT LEFT(title, 1) FROM articles_hash WHERE author_id = 3);
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
left
------
a
(1 row)
(SELECT LEFT(title, 1) FROM articles_hash WHERE author_id = 1)
INTERSECT
(SELECT LEFT(title, 1) FROM articles_hash WHERE author_id = 3);
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
left
------
a
(1 row)
(SELECT LEFT(title, 2) FROM articles_hash WHERE author_id = 1)
EXCEPT
(SELECT LEFT(title, 2) FROM articles_hash WHERE author_id = 3);
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
left
------
at
az
ar
al
(4 rows)
-- union queries are not supported if not router plannable
-- there is an inconsistency on shard pruning between
-- ubuntu/mac disabling log messages for this queries only
SET client_min_messages to 'NOTICE';
(SELECT * FROM articles_hash WHERE author_id = 1)
UNION
(SELECT * FROM articles_hash WHERE author_id = 2);
ERROR: cannot perform distributed planning on this query
DETAIL: Union, Intersect, or Except are currently unsupported
SELECT * FROM (
(SELECT * FROM articles_hash WHERE author_id = 1)
UNION
(SELECT * FROM articles_hash WHERE author_id = 2)) uu;
ERROR: cannot perform distributed planning on this query
DETAIL: Subqueries without group by clause are not supported yet
-- error out for queries with repartition jobs
SELECT *
FROM articles_hash a, articles_hash b
WHERE a.id = b.id AND a.author_id = 1;
ERROR: cannot use real time executor with repartition jobs
HINT: Set citus.task_executor_type to "task-tracker".
-- queries which hit more than 1 shards are not router plannable or executable
-- handled by real-time executor
SELECT *
FROM articles_hash
WHERE author_id >= 1 AND author_id <= 3;
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
3 | 3 | asternal | 10480
11 | 1 | alamo | 1347
13 | 3 | aseyev | 2255
21 | 1 | arcading | 5890
23 | 3 | abhorring | 6799
31 | 1 | athwartships | 7271
33 | 3 | autochrome | 8180
41 | 1 | aznavour | 11814
43 | 3 | affixal | 12723
2 | 2 | abducing | 13642
12 | 2 | archiblast | 18185
22 | 2 | antipope | 2728
32 | 2 | amazon | 11342
42 | 2 | ausable | 15885
(15 rows)
SET citus.task_executor_type TO 'real-time';
-- Test various filtering options for router plannable check
SET client_min_messages to 'DEBUG2';
-- this is definitely single shard
-- and router plannable
SELECT *
FROM articles_hash
WHERE author_id = 1 and author_id >= 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- not router plannable due to or
SELECT *
FROM articles_hash
WHERE author_id = 1 or id = 1;
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- router plannable
SELECT *
FROM articles_hash
WHERE author_id = 1 and (id = 1 or id = 41);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+----------+------------
1 | 1 | arsenous | 9572
41 | 1 | aznavour | 11814
(2 rows)
-- router plannable
SELECT *
FROM articles_hash
WHERE author_id = 1 and (id = random()::int * 0);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
-- not router plannable due to function call on the right side
SELECT *
FROM articles_hash
WHERE author_id = (random()::int * 0 + 1);
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- not router plannable due to or
SELECT *
FROM articles_hash
WHERE author_id = 1 or id = 1;
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- router plannable due to abs(-1) getting converted to 1 by postgresql
SELECT *
FROM articles_hash
WHERE author_id = abs(-1);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- not router plannable due to abs() function
SELECT *
FROM articles_hash
WHERE 1 = abs(author_id);
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- not router plannable due to abs() function
SELECT *
FROM articles_hash
WHERE author_id = abs(author_id - 2);
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- router plannable, function on different field
SELECT *
FROM articles_hash
WHERE author_id = 1 and (id = abs(id - 2));
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+----------+------------
1 | 1 | arsenous | 9572
(1 row)
-- not router plannable due to is true
SELECT *
FROM articles_hash
WHERE (author_id = 1) is true;
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- router plannable, (boolean expression) = true is collapsed to (boolean expression)
SELECT *
FROM articles_hash
WHERE (author_id = 1) = true;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- router plannable, between operator is on another column
SELECT *
FROM articles_hash
WHERE (author_id = 1) and id between 0 and 20;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+----------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
(2 rows)
-- router plannable, partition column expression is and'ed to rest
SELECT *
FROM articles_hash
WHERE (author_id = 1) and (id = 1 or id = 31) and title like '%s';
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
31 | 1 | athwartships | 7271
(2 rows)
-- router plannable, order is changed
SELECT *
FROM articles_hash
WHERE (id = 1 or id = 31) and title like '%s' and (author_id = 1);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
31 | 1 | athwartships | 7271
(2 rows)
-- router plannable
SELECT *
FROM articles_hash
WHERE (title like '%s' or title like 'a%') and (author_id = 1);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- router plannable
SELECT *
FROM articles_hash
WHERE (title like '%s' or title like 'a%') and (author_id = 1) and (word_count < 3000 or word_count > 8000);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+----------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
41 | 1 | aznavour | 11814
(3 rows)
-- window functions are supported if query is router plannable
SELECT LAG(title, 1) over (ORDER BY word_count) prev, title, word_count
FROM articles_hash
WHERE author_id = 5;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
prev | title | word_count
----------+----------+------------
| afrasia | 864
afrasia | adversa | 3164
adversa | antehall | 7707
antehall | aminate | 9089
aminate | aruru | 11389
(5 rows)
SELECT LAG(title, 1) over (ORDER BY word_count) prev, title, word_count
FROM articles_hash
WHERE author_id = 5
ORDER BY word_count DESC;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
prev | title | word_count
----------+----------+------------
aminate | aruru | 11389
antehall | aminate | 9089
adversa | antehall | 7707
afrasia | adversa | 3164
| afrasia | 864
(5 rows)
SELECT id, MIN(id) over (order by word_count)
FROM articles_hash
WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | min
----+-----
11 | 11
21 | 11
31 | 11
1 | 1
41 | 1
(5 rows)
SELECT id, word_count, AVG(word_count) over (order by word_count)
FROM articles_hash
WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | word_count | avg
----+------------+-----------------------
11 | 1347 | 1347.0000000000000000
21 | 5890 | 3618.5000000000000000
31 | 7271 | 4836.0000000000000000
1 | 9572 | 6020.0000000000000000
41 | 11814 | 7178.8000000000000000
(5 rows)
SELECT word_count, rank() OVER (PARTITION BY author_id ORDER BY word_count)
FROM articles_hash
WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
word_count | rank
------------+------
1347 | 1
5890 | 2
7271 | 3
9572 | 4
11814 | 5
(5 rows)
-- window functions are not supported for not router plannable queries
SELECT id, MIN(id) over (order by word_count)
FROM articles_hash
WHERE author_id = 1 or author_id = 2;
ERROR: cannot perform distributed planning on this query
DETAIL: Window functions are currently unsupported
SELECT LAG(title, 1) over (ORDER BY word_count) prev, title, word_count
FROM articles_hash
WHERE author_id = 5 or author_id = 2;
ERROR: cannot perform distributed planning on this query
DETAIL: Window functions are currently unsupported
-- where false queries are router plannable
SELECT *
FROM articles_hash
WHERE false;
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
SELECT *
FROM articles_hash
WHERE author_id = 1 and false;
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
SELECT *
FROM articles_hash
WHERE author_id = 1 and 1=0;
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
SELECT a.author_id as first_author, b.word_count as second_word_count
FROM articles_hash a, articles_single_shard_hash b
WHERE a.author_id = 10 and a.author_id = b.author_id and false;
DEBUG: Creating router plan
DEBUG: Plan is router executable
first_author | second_word_count
--------------+-------------------
(0 rows)
SELECT *
FROM articles_hash
WHERE null;
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
-- where false with immutable function returning false
SELECT *
FROM articles_hash a
WHERE a.author_id = 10 and int4eq(1, 2);
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
SELECT *
FROM articles_hash a
WHERE int4eq(1, 2);
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
SELECT a.author_id as first_author, b.word_count as second_word_count
FROM articles_hash a, articles_single_shard_hash b
WHERE a.author_id = 10 and a.author_id = b.author_id and int4eq(1, 1);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
first_author | second_word_count
--------------+-------------------
10 | 19519
10 | 19519
10 | 19519
10 | 19519
10 | 19519
(5 rows)
SELECT a.author_id as first_author, b.word_count as second_word_count
FROM articles_hash a, articles_single_shard_hash b
WHERE a.author_id = 10 and a.author_id = b.author_id and int4eq(1, 2);
DEBUG: Creating router plan
DEBUG: Plan is router executable
first_author | second_word_count
--------------+-------------------
(0 rows)
-- partition_column is null clause does not prune out any shards,
-- all shards remain after shard pruning, not router plannable
SELECT *
FROM articles_hash a
WHERE a.author_id is null;
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
-- partition_column equals to null clause prunes out all shards
-- no shards after shard pruning, router plannable
SELECT *
FROM articles_hash a
WHERE a.author_id = null;
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
-- stable function returning bool
SELECT *
FROM articles_hash a
WHERE date_ne_timestamp('1954-04-11', '1954-04-11'::timestamp);
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
SELECT a.author_id as first_author, b.word_count as second_word_count
FROM articles_hash a, articles_single_shard_hash b
WHERE a.author_id = 10 and a.author_id = b.author_id and
date_ne_timestamp('1954-04-11', '1954-04-11'::timestamp);
DEBUG: Creating router plan
DEBUG: Plan is router executable
first_author | second_word_count
--------------+-------------------
(0 rows)
-- union/difference /intersection with where false
-- this query was not originally router plannable, addition of 1=0
-- makes it router plannable
(SELECT * FROM articles_hash WHERE author_id = 1)
UNION
(SELECT * FROM articles_hash WHERE author_id = 2 and 1=0);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
11 | 1 | alamo | 1347
41 | 1 | aznavour | 11814
1 | 1 | arsenous | 9572
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
(5 rows)
(SELECT * FROM articles_hash WHERE author_id = 1)
EXCEPT
(SELECT * FROM articles_hash WHERE author_id = 2 and 1=0);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
11 | 1 | alamo | 1347
41 | 1 | aznavour | 11814
(5 rows)
(SELECT * FROM articles_hash WHERE author_id = 1)
INTERSECT
(SELECT * FROM articles_hash WHERE author_id = 2 and 1=0);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
-- CTEs with where false
WITH id_author AS ( SELECT id, author_id FROM articles_hash WHERE author_id = 1),
id_title AS (SELECT id, title from articles_hash WHERE author_id = 1 and 1=0)
SELECT * FROM id_author, id_title WHERE id_author.id = id_title.id;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | id | title
----+-----------+----+-------
(0 rows)
WITH id_author AS ( SELECT id, author_id FROM articles_hash WHERE author_id = 1),
id_title AS (SELECT id, title from articles_hash WHERE author_id = 1)
SELECT * FROM id_author, id_title WHERE id_author.id = id_title.id and 1=0;
DEBUG: predicate pruning for shardId 840001
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | id | title
----+-----------+----+-------
(0 rows)
WITH RECURSIVE hierarchy as (
SELECT *, 1 AS level
FROM company_employees
WHERE company_id = 1 and manager_id = 0
UNION
SELECT ce.*, (h.level+1)
FROM hierarchy h JOIN company_employees ce
ON (h.employee_id = ce.manager_id AND
h.company_id = ce.company_id AND
ce.company_id = 1))
SELECT * FROM hierarchy WHERE LEVEL <= 2 and 1=0;
DEBUG: predicate pruning for shardId 840004
DEBUG: predicate pruning for shardId 840005
DEBUG: predicate pruning for shardId 840006
DEBUG: predicate pruning for shardId 840004
DEBUG: predicate pruning for shardId 840005
DEBUG: predicate pruning for shardId 840006
DEBUG: Creating router plan
DEBUG: Plan is router executable
company_id | employee_id | manager_id | level
------------+-------------+------------+-------
(0 rows)
WITH RECURSIVE hierarchy as (
SELECT *, 1 AS level
FROM company_employees
WHERE company_id = 1 and manager_id = 0
UNION
SELECT ce.*, (h.level+1)
FROM hierarchy h JOIN company_employees ce
ON (h.employee_id = ce.manager_id AND
h.company_id = ce.company_id AND
ce.company_id = 1 AND 1=0))
SELECT * FROM hierarchy WHERE LEVEL <= 2;
DEBUG: predicate pruning for shardId 840004
DEBUG: predicate pruning for shardId 840005
DEBUG: predicate pruning for shardId 840006
DEBUG: Creating router plan
DEBUG: Plan is router executable
company_id | employee_id | manager_id | level
------------+-------------+------------+-------
1 | 1 | 0 | 1
(1 row)
WITH RECURSIVE hierarchy as (
SELECT *, 1 AS level
FROM company_employees
WHERE company_id = 1 and manager_id = 0 AND 1=0
UNION
SELECT ce.*, (h.level+1)
FROM hierarchy h JOIN company_employees ce
ON (h.employee_id = ce.manager_id AND
h.company_id = ce.company_id AND
ce.company_id = 1))
SELECT * FROM hierarchy WHERE LEVEL <= 2;
DEBUG: predicate pruning for shardId 840004
DEBUG: predicate pruning for shardId 840005
DEBUG: predicate pruning for shardId 840006
DEBUG: Creating router plan
DEBUG: Plan is router executable
company_id | employee_id | manager_id | level
------------+-------------+------------+-------
(0 rows)
-- window functions with where false
SELECT word_count, rank() OVER (PARTITION BY author_id ORDER BY word_count)
FROM articles_hash
WHERE author_id = 1 and 1=0;
DEBUG: Creating router plan
DEBUG: Plan is router executable
word_count | rank
------------+------
(0 rows)
-- function calls in WHERE clause with non-relational arguments
SELECT author_id FROM articles_hash
WHERE
substring('hello world', 1, 5) = 'hello'
ORDER BY
author_id
LIMIT 1;
DEBUG: push down of limit count: 1
author_id
-----------
1
(1 row)
-- when expression evaluates to false
SELECT author_id FROM articles_hash
WHERE
substring('hello world', 1, 4) = 'hello'
ORDER BY
author_id
LIMIT 1;
DEBUG: Creating router plan
DEBUG: Plan is router executable
author_id
-----------
(0 rows)
-- following is a bug, function should have been
-- evaluated at master before going to worker
-- need to use a range distributed table here
SELECT master_create_distributed_table('articles_range', 'author_id', 'range');
master_create_distributed_table
---------------------------------
(1 row)
SET citus.shard_replication_factor TO 1;
SELECT master_create_empty_shard('articles_range') AS shard_id \gset
UPDATE pg_dist_shard SET shardmaxvalue = 100, shardminvalue=1 WHERE shardid = :shard_id;
SELECT author_id FROM articles_range
WHERE
substring('articles_range'::regclass::text, 1, 5) = 'hello'
ORDER BY
author_id
LIMIT 1;
DEBUG: push down of limit count: 1
WARNING: relation "public.articles_range" does not exist
CONTEXT: while executing command on localhost:57637
WARNING: relation "public.articles_range" does not exist
CONTEXT: while executing command on localhost:57637
WARNING: relation "public.articles_range" does not exist
CONTEXT: while executing command on localhost:57637
ERROR: failed to execute job 840021
DETAIL: Failure due to failed task 2
-- same query with where false but evaluation left to worker
SELECT author_id FROM articles_range
WHERE
substring('articles_range'::regclass::text, 1, 4) = 'hello'
ORDER BY
author_id
LIMIT 1;
DEBUG: push down of limit count: 1
WARNING: relation "public.articles_range" does not exist
CONTEXT: while executing command on localhost:57637
WARNING: relation "public.articles_range" does not exist
CONTEXT: while executing command on localhost:57637
WARNING: relation "public.articles_range" does not exist
CONTEXT: while executing command on localhost:57637
ERROR: failed to execute job 840022
DETAIL: Failure due to failed task 2
-- same query on router planner with where false but evaluation left to worker
SELECT author_id FROM articles_single_shard_hash
WHERE
substring('articles_single_shard_hash'::regclass::text, 1, 4) = 'hello'
ORDER BY
author_id
LIMIT 1;
DEBUG: Creating router plan
DEBUG: Plan is router executable
WARNING: relation "public.articles_single_shard_hash" does not exist
CONTEXT: while executing command on localhost:57637
ERROR: could not receive query results
SELECT author_id FROM articles_hash
WHERE
author_id = 1
AND substring('articles_hash'::regclass::text, 1, 5) = 'hello'
ORDER BY
author_id
LIMIT 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
WARNING: relation "public.articles_hash" does not exist
CONTEXT: while executing command on localhost:57637
ERROR: could not receive query results
-- create a dummy function to be used in filtering
CREATE OR REPLACE FUNCTION someDummyFunction(regclass)
RETURNS text AS
$$
BEGIN
RETURN md5($1::text);
END;
$$ LANGUAGE 'plpgsql' IMMUTABLE;
-- not router plannable, returns all rows
SELECT * FROM articles_hash
WHERE
someDummyFunction('articles_hash') = md5('articles_hash')
ORDER BY
author_id, id
LIMIT 5;
DEBUG: push down of limit count: 5
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- router plannable, errors
SELECT * FROM articles_hash
WHERE
someDummyFunction('articles_hash') = md5('articles_hash') AND author_id = 1
ORDER BY
author_id, id
LIMIT 5;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
WARNING: relation "public.articles_hash" does not exist
CONTEXT: while executing command on localhost:57637
ERROR: could not receive query results
-- temporarily turn off debug messages before dropping the function
SET client_min_messages TO 'NOTICE';
DROP FUNCTION someDummyFunction(regclass);
SET client_min_messages TO 'DEBUG2';
-- complex query hitting a single shard
SELECT
count(DISTINCT CASE
WHEN
word_count > 100
THEN
id
ELSE
NULL
END) as c
FROM
articles_hash
WHERE
author_id = 5;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
c
---
5
(1 row)
-- same query is not router plannable if hits multiple shards
SELECT
count(DISTINCT CASE
WHEN
word_count > 100
THEN
id
ELSE
NULL
END) as c
FROM
articles_hash
GROUP BY
author_id;
c
---
4
5
5
5
5
5
5
5
5
5
(10 rows)
-- queries inside transactions can be router plannable
BEGIN;
SELECT *
FROM articles_hash
WHERE author_id = 1
ORDER BY id;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
END;
-- cursor queries are router plannable
BEGIN;
DECLARE test_cursor CURSOR FOR
SELECT *
FROM articles_hash
WHERE author_id = 1
ORDER BY id;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
FETCH test_cursor;
id | author_id | title | word_count
----+-----------+----------+------------
1 | 1 | arsenous | 9572
(1 row)
FETCH ALL test_cursor;
id | author_id | title | word_count
----+-----------+--------------+------------
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(4 rows)
FETCH test_cursor; -- fetch one row after the last
id | author_id | title | word_count
----+-----------+-------+------------
(0 rows)
END;
-- queries inside copy can be router plannable
COPY (
SELECT *
FROM articles_hash
WHERE author_id = 1
ORDER BY id) TO STDOUT;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
1 1 arsenous 9572
11 1 alamo 1347
21 1 arcading 5890
31 1 athwartships 7271
41 1 aznavour 11814
-- table creation queries inside can be router plannable
CREATE TEMP TABLE temp_articles_hash as
SELECT *
FROM articles_hash
WHERE author_id = 1
ORDER BY id;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
-- router plannable queries may include filter for aggragates
SELECT count(*), count(*) FILTER (WHERE id < 3)
FROM articles_hash
WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
count | count
-------+-------
5 | 1
(1 row)
-- non-router plannable queries also support filters
SELECT count(*), count(*) FILTER (WHERE id < 3)
FROM articles_hash
WHERE author_id = 1 or author_id = 2;
count | count
-------+-------
10 | 2
(1 row)
-- prepare queries can be router plannable
PREPARE author_1_articles as
SELECT *
FROM articles_hash
WHERE author_id = 1;
EXECUTE author_1_articles;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- parametric prepare queries can be router plannable
PREPARE author_articles(int) as
SELECT *
FROM articles_hash
WHERE author_id = $1;
EXECUTE author_articles(1);
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
-- queries inside plpgsql functions could be router plannable
CREATE OR REPLACE FUNCTION author_articles_max_id() RETURNS int AS $$
DECLARE
max_id integer;
BEGIN
SELECT MAX(id) FROM articles_hash ah
WHERE author_id = 1
into max_id;
return max_id;
END;
$$ LANGUAGE plpgsql;
SELECT author_articles_max_id();
DEBUG: predicate pruning for shardId 840001
CONTEXT: SQL statement "SELECT MAX(id) FROM articles_hash ah
WHERE author_id = 1"
PL/pgSQL function author_articles_max_id() line 5 at SQL statement
DEBUG: predicate pruning for shardId 840001
CONTEXT: SQL statement "SELECT MAX(id) FROM articles_hash ah
WHERE author_id = 1"
PL/pgSQL function author_articles_max_id() line 5 at SQL statement
DEBUG: predicate pruning for shardId 840001
CONTEXT: SQL statement "SELECT MAX(id) FROM articles_hash ah
WHERE author_id = 1"
PL/pgSQL function author_articles_max_id() line 5 at SQL statement
DEBUG: Creating router plan
CONTEXT: SQL statement "SELECT MAX(id) FROM articles_hash ah
WHERE author_id = 1"
PL/pgSQL function author_articles_max_id() line 5 at SQL statement
DEBUG: Plan is router executable
CONTEXT: SQL statement "SELECT MAX(id) FROM articles_hash ah
WHERE author_id = 1"
PL/pgSQL function author_articles_max_id() line 5 at SQL statement
author_articles_max_id
------------------------
41
(1 row)
-- check that function returning setof query are router plannable
CREATE OR REPLACE FUNCTION author_articles_id_word_count() RETURNS TABLE(id bigint, word_count int) AS $$
DECLARE
BEGIN
RETURN QUERY
SELECT ah.id, ah.word_count
FROM articles_hash ah
WHERE author_id = 1;
END;
$$ LANGUAGE plpgsql;
SELECT * FROM author_articles_id_word_count();
DEBUG: predicate pruning for shardId 840001
CONTEXT: SQL statement "SELECT ah.id, ah.word_count
FROM articles_hash ah
WHERE author_id = 1"
PL/pgSQL function author_articles_id_word_count() line 4 at RETURN QUERY
DEBUG: Creating router plan
CONTEXT: SQL statement "SELECT ah.id, ah.word_count
FROM articles_hash ah
WHERE author_id = 1"
PL/pgSQL function author_articles_id_word_count() line 4 at RETURN QUERY
DEBUG: Plan is router executable
CONTEXT: PL/pgSQL function author_articles_id_word_count() line 4 at RETURN QUERY
id | word_count
----+------------
1 | 9572
11 | 1347
21 | 5890
31 | 7271
41 | 11814
(5 rows)
-- materialized views can be created for router plannable queries
CREATE MATERIALIZED VIEW mv_articles_hash AS
SELECT * FROM articles_hash WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
SELECT * FROM mv_articles_hash;
id | author_id | title | word_count
----+-----------+--------------+------------
1 | 1 | arsenous | 9572
11 | 1 | alamo | 1347
21 | 1 | arcading | 5890
31 | 1 | athwartships | 7271
41 | 1 | aznavour | 11814
(5 rows)
CREATE MATERIALIZED VIEW mv_articles_hash_error AS
SELECT * FROM articles_hash WHERE author_id in (1,2);
NOTICE: cannot use shard pruning with ANY/ALL (array expression)
HINT: Consider rewriting the expression with OR/AND clauses.
NOTICE: cannot use shard pruning with ANY/ALL (array expression)
HINT: Consider rewriting the expression with OR/AND clauses.
ERROR: cannot create temporary table within security-restricted operation
-- router planner/executor is now enabled for task-tracker executor
SET citus.task_executor_type to 'task-tracker';
SELECT id
FROM articles_hash
WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id
----
1
11
21
31
41
(5 rows)
-- insert query is router plannable even under task-tracker
INSERT INTO articles_hash VALUES (51, 1, 'amateus', 1814);
DEBUG: Creating router plan
DEBUG: Plan is router executable
-- verify insert is successfull (not router plannable and executable)
SELECT id
FROM articles_hash
WHERE author_id = 1;
DEBUG: predicate pruning for shardId 840001
DEBUG: Creating router plan
DEBUG: Plan is router executable
id
----
1
11
21
31
41
51
(6 rows)
SET client_min_messages to 'NOTICE';
DROP FUNCTION author_articles_max_id();
DROP FUNCTION author_articles_id_word_count();
DROP MATERIALIZED VIEW mv_articles_hash;
DROP TABLE articles_hash;
DROP TABLE articles_single_shard_hash;
DROP TABLE authors_hash;
DROP TABLE company_employees;
DROP TABLE articles_range;
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