mirror of https://github.com/citusdata/citus.git
910 lines
28 KiB
PL/PgSQL
910 lines
28 KiB
PL/PgSQL
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ALTER SEQUENCE pg_catalog.pg_dist_shardid_seq RESTART 840000;
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ALTER SEQUENCE pg_catalog.pg_dist_jobid_seq RESTART 840000;
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-- ===================================================================
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-- test router planner functionality for single shard select queries
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-- ===================================================================
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CREATE TABLE articles_hash (
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id bigint NOT NULL,
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author_id bigint NOT NULL,
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title varchar(20) NOT NULL,
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word_count integer
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);
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CREATE TABLE articles_range (
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id bigint NOT NULL,
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author_id bigint NOT NULL,
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title varchar(20) NOT NULL,
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word_count integer
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);
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-- Check for the existence of line 'DEBUG: Creating router plan'
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-- to determine if router planner is used.
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-- this table is used in a CTE test
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CREATE TABLE authors_hash ( name text, id bigint );
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-- this table is used in router executor tests
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CREATE TABLE articles_single_shard_hash (LIKE articles_hash);
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SELECT master_create_distributed_table('articles_hash', 'author_id', 'hash');
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SELECT master_create_distributed_table('articles_single_shard_hash', 'author_id', 'hash');
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-- test when a table is distributed but no shards created yet
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SELECT count(*) from articles_hash;
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SELECT master_create_worker_shards('articles_hash', 2, 1);
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SELECT master_create_worker_shards('articles_single_shard_hash', 1, 1);
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-- create a bunch of test data
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INSERT INTO articles_hash VALUES ( 1, 1, 'arsenous', 9572);
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INSERT INTO articles_hash VALUES ( 2, 2, 'abducing', 13642);
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INSERT INTO articles_hash VALUES ( 3, 3, 'asternal', 10480);
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INSERT INTO articles_hash VALUES ( 4, 4, 'altdorfer', 14551);
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INSERT INTO articles_hash VALUES ( 5, 5, 'aruru', 11389);
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INSERT INTO articles_hash VALUES ( 6, 6, 'atlases', 15459);
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INSERT INTO articles_hash VALUES ( 7, 7, 'aseptic', 12298);
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INSERT INTO articles_hash VALUES ( 8, 8, 'agatized', 16368);
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INSERT INTO articles_hash VALUES ( 9, 9, 'alligate', 438);
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INSERT INTO articles_hash VALUES (10, 10, 'aggrandize', 17277);
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INSERT INTO articles_hash VALUES (11, 1, 'alamo', 1347);
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INSERT INTO articles_hash VALUES (12, 2, 'archiblast', 18185);
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INSERT INTO articles_hash VALUES (13, 3, 'aseyev', 2255);
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INSERT INTO articles_hash VALUES (14, 4, 'andesite', 19094);
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INSERT INTO articles_hash VALUES (15, 5, 'adversa', 3164);
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INSERT INTO articles_hash VALUES (16, 6, 'allonym', 2);
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INSERT INTO articles_hash VALUES (17, 7, 'auriga', 4073);
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INSERT INTO articles_hash VALUES (18, 8, 'assembly', 911);
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INSERT INTO articles_hash VALUES (19, 9, 'aubergiste', 4981);
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INSERT INTO articles_hash VALUES (20, 10, 'absentness', 1820);
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INSERT INTO articles_hash VALUES (21, 1, 'arcading', 5890);
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INSERT INTO articles_hash VALUES (22, 2, 'antipope', 2728);
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INSERT INTO articles_hash VALUES (23, 3, 'abhorring', 6799);
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INSERT INTO articles_hash VALUES (24, 4, 'audacious', 3637);
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INSERT INTO articles_hash VALUES (25, 5, 'antehall', 7707);
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INSERT INTO articles_hash VALUES (26, 6, 'abington', 4545);
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INSERT INTO articles_hash VALUES (27, 7, 'arsenous', 8616);
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INSERT INTO articles_hash VALUES (28, 8, 'aerophyte', 5454);
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INSERT INTO articles_hash VALUES (29, 9, 'amateur', 9524);
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INSERT INTO articles_hash VALUES (30, 10, 'andelee', 6363);
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INSERT INTO articles_hash VALUES (31, 1, 'athwartships', 7271);
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INSERT INTO articles_hash VALUES (32, 2, 'amazon', 11342);
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INSERT INTO articles_hash VALUES (33, 3, 'autochrome', 8180);
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INSERT INTO articles_hash VALUES (34, 4, 'amnestied', 12250);
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INSERT INTO articles_hash VALUES (35, 5, 'aminate', 9089);
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INSERT INTO articles_hash VALUES (36, 6, 'ablation', 13159);
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INSERT INTO articles_hash VALUES (37, 7, 'archduchies', 9997);
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INSERT INTO articles_hash VALUES (38, 8, 'anatine', 14067);
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INSERT INTO articles_hash VALUES (39, 9, 'anchises', 10906);
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INSERT INTO articles_hash VALUES (40, 10, 'attemper', 14976);
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INSERT INTO articles_hash VALUES (41, 1, 'aznavour', 11814);
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INSERT INTO articles_hash VALUES (42, 2, 'ausable', 15885);
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INSERT INTO articles_hash VALUES (43, 3, 'affixal', 12723);
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INSERT INTO articles_hash VALUES (44, 4, 'anteport', 16793);
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INSERT INTO articles_hash VALUES (45, 5, 'afrasia', 864);
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INSERT INTO articles_hash VALUES (46, 6, 'atlanta', 17702);
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INSERT INTO articles_hash VALUES (47, 7, 'abeyance', 1772);
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INSERT INTO articles_hash VALUES (48, 8, 'alkylic', 18610);
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INSERT INTO articles_hash VALUES (49, 9, 'anyone', 2681);
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INSERT INTO articles_hash VALUES (50, 10, 'anjanette', 19519);
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SET citus.task_executor_type TO 'real-time';
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SET citus.large_table_shard_count TO 2;
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SET client_min_messages TO 'DEBUG2';
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-- insert a single row for the test
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INSERT INTO articles_single_shard_hash VALUES (50, 10, 'anjanette', 19519);
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-- single-shard tests
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-- test simple select for a single row
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SELECT * FROM articles_hash WHERE author_id = 10 AND id = 50;
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-- get all titles by a single author
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SELECT title FROM articles_hash WHERE author_id = 10;
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-- try ordering them by word count
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SELECT title, word_count FROM articles_hash
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WHERE author_id = 10
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ORDER BY word_count DESC NULLS LAST;
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-- look at last two articles by an author
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SELECT title, id FROM articles_hash
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WHERE author_id = 5
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ORDER BY id
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LIMIT 2;
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-- find all articles by two authors in same shard
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-- but plan is not router executable due to order by
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SELECT title, author_id FROM articles_hash
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WHERE author_id = 7 OR author_id = 8
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ORDER BY author_id ASC, id;
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-- same query is router executable with no order by
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SELECT title, author_id FROM articles_hash
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WHERE author_id = 7 OR author_id = 8;
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-- add in some grouping expressions, still on same shard
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-- having queries unsupported in Citus
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SELECT author_id, sum(word_count) AS corpus_size FROM articles_hash
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WHERE author_id = 1 OR author_id = 7 OR author_id = 8 OR author_id = 10
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GROUP BY author_id
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HAVING sum(word_count) > 1000
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ORDER BY sum(word_count) DESC;
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-- however having clause is supported if it goes to a single shard
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SELECT author_id, sum(word_count) AS corpus_size FROM articles_hash
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WHERE author_id = 1
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GROUP BY author_id
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HAVING sum(word_count) > 1000
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ORDER BY sum(word_count) DESC;
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-- query is a single shard query but can't do shard pruning,
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-- not router-plannable due to <= and IN
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SELECT * FROM articles_hash WHERE author_id <= 1;
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SELECT * FROM articles_hash WHERE author_id IN (1, 3);
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-- queries with CTEs are supported
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WITH first_author AS ( SELECT id FROM articles_hash WHERE author_id = 1)
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SELECT * FROM first_author;
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-- queries with CTEs are supported even if CTE is not referenced inside query
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WITH first_author AS ( SELECT id FROM articles_hash WHERE author_id = 1)
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SELECT title FROM articles_hash WHERE author_id = 1;
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-- two CTE joins are supported if they go to the same worker
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WITH id_author AS ( SELECT id, author_id FROM articles_hash WHERE author_id = 1),
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id_title AS (SELECT id, title from articles_hash WHERE author_id = 1)
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SELECT * FROM id_author, id_title WHERE id_author.id = id_title.id;
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WITH id_author AS ( SELECT id, author_id FROM articles_hash WHERE author_id = 1),
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id_title AS (SELECT id, title from articles_hash WHERE author_id = 3)
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SELECT * FROM id_author, id_title WHERE id_author.id = id_title.id;
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-- CTE joins are not supported if table shards are at different workers
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WITH id_author AS ( SELECT id, author_id FROM articles_hash WHERE author_id = 1),
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id_title AS (SELECT id, title from articles_hash WHERE author_id = 2)
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SELECT * FROM id_author, id_title WHERE id_author.id = id_title.id;
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-- recursive CTEs are supported when filtered on partition column
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CREATE TABLE company_employees (company_id int, employee_id int, manager_id int);
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SELECT master_create_distributed_table('company_employees', 'company_id', 'hash');
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SELECT master_create_worker_shards('company_employees', 4, 1);
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INSERT INTO company_employees values(1, 1, 0);
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INSERT INTO company_employees values(1, 2, 1);
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INSERT INTO company_employees values(1, 3, 1);
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INSERT INTO company_employees values(1, 4, 2);
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INSERT INTO company_employees values(1, 5, 4);
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INSERT INTO company_employees values(3, 1, 0);
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INSERT INTO company_employees values(3, 15, 1);
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INSERT INTO company_employees values(3, 3, 1);
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-- find employees at top 2 level within company hierarchy
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WITH RECURSIVE hierarchy as (
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SELECT *, 1 AS level
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FROM company_employees
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WHERE company_id = 1 and manager_id = 0
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UNION
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SELECT ce.*, (h.level+1)
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FROM hierarchy h JOIN company_employees ce
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ON (h.employee_id = ce.manager_id AND
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h.company_id = ce.company_id AND
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ce.company_id = 1))
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SELECT * FROM hierarchy WHERE LEVEL <= 2;
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-- query becomes not router plannble and gets rejected
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-- if filter on company is dropped
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WITH RECURSIVE hierarchy as (
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SELECT *, 1 AS level
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FROM company_employees
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WHERE company_id = 1 and manager_id = 0
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UNION
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SELECT ce.*, (h.level+1)
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FROM hierarchy h JOIN company_employees ce
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ON (h.employee_id = ce.manager_id AND
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h.company_id = ce.company_id))
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SELECT * FROM hierarchy WHERE LEVEL <= 2;
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-- logically wrong query, query involves different shards
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-- from the same table
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WITH RECURSIVE hierarchy as (
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SELECT *, 1 AS level
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FROM company_employees
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WHERE company_id = 3 and manager_id = 0
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UNION
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SELECT ce.*, (h.level+1)
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FROM hierarchy h JOIN company_employees ce
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ON (h.employee_id = ce.manager_id AND
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h.company_id = ce.company_id AND
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ce.company_id = 2))
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SELECT * FROM hierarchy WHERE LEVEL <= 2;
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-- grouping sets are supported on single shard
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SELECT
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id, substring(title, 2, 1) AS subtitle, count(*)
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FROM articles_hash
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WHERE author_id = 1 or author_id = 3
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GROUP BY GROUPING SETS ((id),(subtitle));
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-- grouping sets are not supported on multiple shards
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SELECT
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id, substring(title, 2, 1) AS subtitle, count(*)
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FROM articles_hash
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WHERE author_id = 1 or author_id = 2
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GROUP BY GROUPING SETS ((id),(subtitle));
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-- queries which involve functions in FROM clause are supported if it goes to a single worker.
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SELECT * FROM articles_hash, position('om' in 'Thomas') WHERE author_id = 1;
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SELECT * FROM articles_hash, position('om' in 'Thomas') WHERE author_id = 1 or author_id = 3;
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-- they are not supported if multiple workers are involved
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SELECT * FROM articles_hash, position('om' in 'Thomas') WHERE author_id = 1 or author_id = 2;
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-- subqueries are not supported in WHERE clause in Citus
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SELECT * FROM articles_hash WHERE author_id IN (SELECT id FROM authors_hash WHERE name LIKE '%a');
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SELECT * FROM articles_hash WHERE author_id IN (SELECT author_id FROM articles_hash WHERE author_id = 1 or author_id = 3);
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SELECT * FROM articles_hash WHERE author_id = (SELECT 1);
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-- unless the query can be transformed into a join
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SELECT * FROM articles_hash
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WHERE author_id IN (SELECT author_id FROM articles_hash WHERE author_id = 2)
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ORDER BY articles_hash.id;
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-- subqueries are supported in FROM clause but they are not router plannable
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SELECT articles_hash.id,test.word_count
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FROM articles_hash, (SELECT id, word_count FROM articles_hash) AS test WHERE test.id = articles_hash.id
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ORDER BY articles_hash.id;
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SELECT articles_hash.id,test.word_count
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FROM articles_hash, (SELECT id, word_count FROM articles_hash) AS test
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WHERE test.id = articles_hash.id and articles_hash.author_id = 1
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ORDER BY articles_hash.id;
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-- subqueries are not supported in SELECT clause
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SELECT a.title AS name, (SELECT a2.id FROM articles_single_shard_hash a2 WHERE a.id = a2.id LIMIT 1)
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AS special_price FROM articles_hash a;
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-- simple lookup query
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SELECT *
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FROM articles_hash
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WHERE author_id = 1;
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-- below query hits a single shard, router plannable
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SELECT *
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FROM articles_hash
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WHERE author_id = 1 OR author_id = 17;
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-- below query hits two shards, not router plannable + not router executable
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-- handled by real-time executor
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SELECT *
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FROM articles_hash
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WHERE author_id = 1 OR author_id = 18;
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-- rename the output columns
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SELECT id as article_id, word_count * id as random_value
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FROM articles_hash
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WHERE author_id = 1;
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-- we can push down co-located joins to a single worker
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SELECT a.author_id as first_author, b.word_count as second_word_count
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FROM articles_hash a, articles_hash b
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WHERE a.author_id = 10 and a.author_id = b.author_id
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LIMIT 3;
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-- following join is router plannable since the same worker
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-- has both shards
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SELECT a.author_id as first_author, b.word_count as second_word_count
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FROM articles_hash a, articles_single_shard_hash b
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WHERE a.author_id = 10 and a.author_id = b.author_id
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LIMIT 3;
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-- following join is not router plannable since there are no
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-- workers containing both shards, added a CTE to make this fail
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-- at logical planner
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WITH single_shard as (SELECT * FROM articles_single_shard_hash)
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SELECT a.author_id as first_author, b.word_count as second_word_count
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FROM articles_hash a, single_shard b
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WHERE a.author_id = 2 and a.author_id = b.author_id
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LIMIT 3;
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-- single shard select with limit is router plannable
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SELECT *
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FROM articles_hash
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WHERE author_id = 1
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LIMIT 3;
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-- single shard select with limit + offset is router plannable
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SELECT *
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FROM articles_hash
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WHERE author_id = 1
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LIMIT 2
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OFFSET 1;
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-- single shard select with limit + offset + order by is router plannable
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SELECT *
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FROM articles_hash
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WHERE author_id = 1
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ORDER BY id desc
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LIMIT 2
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OFFSET 1;
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-- single shard select with group by on non-partition column is router plannable
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SELECT id
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FROM articles_hash
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WHERE author_id = 1
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GROUP BY id
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ORDER BY id;
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-- single shard select with distinct is router plannable
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SELECT DISTINCT id
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FROM articles_hash
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WHERE author_id = 1
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ORDER BY id;
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-- single shard aggregate is router plannable
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SELECT avg(word_count)
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FROM articles_hash
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WHERE author_id = 2;
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-- max, min, sum, count are router plannable on single shard
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SELECT max(word_count) as max, min(word_count) as min,
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sum(word_count) as sum, count(word_count) as cnt
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FROM articles_hash
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WHERE author_id = 2;
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-- queries with aggregates and group by supported on single shard
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SELECT max(word_count)
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FROM articles_hash
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WHERE author_id = 1
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GROUP BY author_id;
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-- router plannable union queries are supported
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(SELECT * FROM articles_hash WHERE author_id = 1)
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UNION
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(SELECT * FROM articles_hash WHERE author_id = 3);
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SELECT * FROM (
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(SELECT * FROM articles_hash WHERE author_id = 1)
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UNION
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(SELECT * FROM articles_hash WHERE author_id = 3)) uu;
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(SELECT LEFT(title, 1) FROM articles_hash WHERE author_id = 1)
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UNION
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(SELECT LEFT(title, 1) FROM articles_hash WHERE author_id = 3);
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(SELECT LEFT(title, 1) FROM articles_hash WHERE author_id = 1)
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INTERSECT
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(SELECT LEFT(title, 1) FROM articles_hash WHERE author_id = 3);
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(SELECT LEFT(title, 2) FROM articles_hash WHERE author_id = 1)
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EXCEPT
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(SELECT LEFT(title, 2) FROM articles_hash WHERE author_id = 3);
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-- union queries are not supported if not router plannable
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-- there is an inconsistency on shard pruning between
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-- ubuntu/mac disabling log messages for this queries only
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SET client_min_messages to 'NOTICE';
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(SELECT * FROM articles_hash WHERE author_id = 1)
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UNION
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(SELECT * FROM articles_hash WHERE author_id = 2);
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SELECT * FROM (
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(SELECT * FROM articles_hash WHERE author_id = 1)
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UNION
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(SELECT * FROM articles_hash WHERE author_id = 2)) uu;
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-- error out for queries with repartition jobs
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SELECT *
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FROM articles_hash a, articles_hash b
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WHERE a.id = b.id AND a.author_id = 1;
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-- queries which hit more than 1 shards are not router plannable or executable
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-- handled by real-time executor
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SELECT *
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FROM articles_hash
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WHERE author_id >= 1 AND author_id <= 3;
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SET citus.task_executor_type TO 'real-time';
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-- Test various filtering options for router plannable check
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SET client_min_messages to 'DEBUG2';
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-- this is definitely single shard
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-- and router plannable
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SELECT *
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FROM articles_hash
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WHERE author_id = 1 and author_id >= 1;
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-- not router plannable due to or
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SELECT *
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FROM articles_hash
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WHERE author_id = 1 or id = 1;
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-- router plannable
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SELECT *
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FROM articles_hash
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WHERE author_id = 1 and (id = 1 or id = 41);
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-- router plannable
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SELECT *
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FROM articles_hash
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WHERE author_id = 1 and (id = random()::int * 0);
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-- not router plannable due to function call on the right side
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SELECT *
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FROM articles_hash
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WHERE author_id = (random()::int * 0 + 1);
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-- not router plannable due to or
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SELECT *
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FROM articles_hash
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WHERE author_id = 1 or id = 1;
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-- router plannable due to abs(-1) getting converted to 1 by postgresql
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SELECT *
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FROM articles_hash
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WHERE author_id = abs(-1);
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-- not router plannable due to abs() function
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SELECT *
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FROM articles_hash
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WHERE 1 = abs(author_id);
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-- not router plannable due to abs() function
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SELECT *
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FROM articles_hash
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WHERE author_id = abs(author_id - 2);
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-- router plannable, function on different field
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SELECT *
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FROM articles_hash
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WHERE author_id = 1 and (id = abs(id - 2));
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-- not router plannable due to is true
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE (author_id = 1) is true;
|
|
|
|
-- router plannable, (boolean expression) = true is collapsed to (boolean expression)
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE (author_id = 1) = true;
|
|
|
|
-- router plannable, between operator is on another column
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE (author_id = 1) and id between 0 and 20;
|
|
|
|
-- 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';
|
|
|
|
-- router plannable, order is changed
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE (id = 1 or id = 31) and title like '%s' and (author_id = 1);
|
|
|
|
-- router plannable
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE (title like '%s' or title like 'a%') and (author_id = 1);
|
|
|
|
-- 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);
|
|
|
|
-- 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;
|
|
|
|
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;
|
|
|
|
SELECT id, MIN(id) over (order by word_count)
|
|
FROM articles_hash
|
|
WHERE author_id = 1;
|
|
|
|
SELECT id, word_count, AVG(word_count) over (order by word_count)
|
|
FROM articles_hash
|
|
WHERE author_id = 1;
|
|
|
|
SELECT word_count, rank() OVER (PARTITION BY author_id ORDER BY word_count)
|
|
FROM articles_hash
|
|
WHERE author_id = 1;
|
|
|
|
-- 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;
|
|
|
|
SELECT LAG(title, 1) over (ORDER BY word_count) prev, title, word_count
|
|
FROM articles_hash
|
|
WHERE author_id = 5 or author_id = 2;
|
|
|
|
-- where false queries are router plannable
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE false;
|
|
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE author_id = 1 and false;
|
|
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE author_id = 1 and 1=0;
|
|
|
|
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;
|
|
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE null;
|
|
|
|
-- where false with immutable function returning false
|
|
SELECT *
|
|
FROM articles_hash a
|
|
WHERE a.author_id = 10 and int4eq(1, 2);
|
|
|
|
SELECT *
|
|
FROM articles_hash a
|
|
WHERE int4eq(1, 2);
|
|
|
|
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);
|
|
|
|
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);
|
|
|
|
-- 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;
|
|
|
|
-- 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;
|
|
|
|
-- stable function returning bool
|
|
SELECT *
|
|
FROM articles_hash a
|
|
WHERE date_ne_timestamp('1954-04-11', '1954-04-11'::timestamp);
|
|
|
|
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);
|
|
-- 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);
|
|
|
|
(SELECT * FROM articles_hash WHERE author_id = 1)
|
|
EXCEPT
|
|
(SELECT * FROM articles_hash WHERE author_id = 2 and 1=0);
|
|
|
|
(SELECT * FROM articles_hash WHERE author_id = 1)
|
|
INTERSECT
|
|
(SELECT * FROM articles_hash WHERE author_id = 2 and 1=0);
|
|
|
|
-- 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;
|
|
|
|
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;
|
|
|
|
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;
|
|
|
|
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;
|
|
|
|
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;
|
|
|
|
|
|
-- 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;
|
|
|
|
-- 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;
|
|
|
|
-- when expression evaluates to false
|
|
SELECT author_id FROM articles_hash
|
|
WHERE
|
|
substring('hello world', 1, 4) = 'hello'
|
|
ORDER BY
|
|
author_id
|
|
LIMIT 1;
|
|
|
|
-- 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');
|
|
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;
|
|
|
|
-- 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;
|
|
|
|
-- 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;
|
|
|
|
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;
|
|
|
|
-- 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;
|
|
|
|
-- 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;
|
|
|
|
-- 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;
|
|
|
|
-- 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;
|
|
|
|
-- queries inside transactions can be router plannable
|
|
BEGIN;
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE author_id = 1
|
|
ORDER BY id;
|
|
END;
|
|
|
|
-- cursor queries are router plannable
|
|
BEGIN;
|
|
DECLARE test_cursor CURSOR FOR
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE author_id = 1
|
|
ORDER BY id;
|
|
FETCH test_cursor;
|
|
FETCH ALL test_cursor;
|
|
FETCH test_cursor; -- fetch one row after the last
|
|
END;
|
|
|
|
-- queries inside copy can be router plannable
|
|
COPY (
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE author_id = 1
|
|
ORDER BY id) TO STDOUT;
|
|
|
|
-- 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;
|
|
|
|
-- router plannable queries may include filter for aggragates
|
|
SELECT count(*), count(*) FILTER (WHERE id < 3)
|
|
FROM articles_hash
|
|
WHERE author_id = 1;
|
|
|
|
-- 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;
|
|
|
|
-- prepare queries can be router plannable
|
|
PREPARE author_1_articles as
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE author_id = 1;
|
|
|
|
EXECUTE author_1_articles;
|
|
|
|
-- parametric prepare queries can be router plannable
|
|
PREPARE author_articles(int) as
|
|
SELECT *
|
|
FROM articles_hash
|
|
WHERE author_id = $1;
|
|
|
|
EXECUTE author_articles(1);
|
|
|
|
-- 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();
|
|
|
|
-- 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();
|
|
|
|
-- materialized views can be created for router plannable queries
|
|
CREATE MATERIALIZED VIEW mv_articles_hash AS
|
|
SELECT * FROM articles_hash WHERE author_id = 1;
|
|
|
|
SELECT * FROM mv_articles_hash;
|
|
|
|
CREATE MATERIALIZED VIEW mv_articles_hash_error AS
|
|
SELECT * FROM articles_hash WHERE author_id in (1,2);
|
|
|
|
-- 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;
|
|
|
|
-- insert query is router plannable even under task-tracker
|
|
INSERT INTO articles_hash VALUES (51, 1, 'amateus', 1814);
|
|
|
|
-- verify insert is successfull (not router plannable and executable)
|
|
SELECT id
|
|
FROM articles_hash
|
|
WHERE author_id = 1;
|
|
|
|
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;
|