citus/src/test/regress/sql/multi_subquery_misc.sql

241 lines
6.7 KiB
PL/PgSQL

-- multi subquery pushdown misc aims to test subquery pushdown queries with
-- (i) Prepared statements
-- (ii) PL/PGSQL functions
-- (iii) SQL functions
-- the tables that are used depends to multi_insert_select_behavioral_analytics_create_table.sql
-- We don't need shard id sequence here, so commented out to prevent conflicts with concurrent tests
SET citus.enable_router_execution TO false;
PREPARE prepared_subquery_1 AS
SELECT
user_id,
user_lastseen,
array_length(event_array, 1)
FROM (
SELECT
user_id,
max(u.time) as user_lastseen,
array_agg(event_type ORDER BY u.time) AS event_array
FROM (
SELECT user_id, time
FROM users_table
WHERE
user_id >= 1 AND
user_id <= 3 AND
users_table.value_1 > 1 AND users_table.value_1 < 3
) u LEFT JOIN LATERAL (
SELECT event_type, time
FROM events_table
WHERE user_id = u.user_id AND
events_table.event_type > 1 AND events_table.event_type < 3
) t ON true
GROUP BY user_id
) AS shard_union
ORDER BY user_lastseen DESC, user_id;
EXECUTE prepared_subquery_1;
PREPARE prepared_subquery_2(int, int) AS
SELECT
user_id,
user_lastseen,
array_length(event_array, 1)
FROM (
SELECT
user_id,
max(u.time) as user_lastseen,
array_agg(event_type ORDER BY u.time) AS event_array
FROM (
SELECT user_id, time
FROM users_table
WHERE
user_id >= $1 AND
user_id <= $2 AND
users_table.value_1 > 1 AND users_table.value_1 < 3
) u LEFT JOIN LATERAL (
SELECT event_type, time
FROM events_table
WHERE user_id = u.user_id AND
events_table.event_type > 1 AND events_table.event_type < 3
) t ON true
GROUP BY user_id
) AS shard_union
ORDER BY user_lastseen DESC, user_id;
-- should be fine with more than five executions
EXECUTE prepared_subquery_2(1, 3);
EXECUTE prepared_subquery_2(1, 3);
EXECUTE prepared_subquery_2(1, 3);
EXECUTE prepared_subquery_2(1, 3);
EXECUTE prepared_subquery_2(1, 3);
EXECUTE prepared_subquery_2(1, 3);
EXECUTE prepared_subquery_2(1, 3);
-- prepared statements with subqueries in WHERE clause
PREPARE prepared_subquery_3(int, int, int, int, int, int) AS
SELECT user_id
FROM users_table
WHERE user_id IN (SELECT user_id FROM users_table WHERE value_1 >= $4 AND value_1 <= $3)
AND user_id IN (SELECT user_id FROM users_table WHERE value_1 >= $5 AND value_1 <= $6)
AND user_id IN (SELECT user_id FROM users_table WHERE value_1 >= $1 AND value_1 <= $2)
GROUP BY
user_id
ORDER BY
user_id DESC
LIMIT 5;
-- enough times (6+) to actually use prepared statements
EXECUTE prepared_subquery_3(4, 5, 1, 0, 2, 3);
EXECUTE prepared_subquery_3(4, 5, 1, 0, 2, 3);
EXECUTE prepared_subquery_3(4, 5, 1, 0, 2, 3);
EXECUTE prepared_subquery_3(4, 5, 1, 0, 2, 3);
EXECUTE prepared_subquery_3(4, 5, 1, 0, 2, 3);
EXECUTE prepared_subquery_3(4, 5, 1, 0, 2, 3);
CREATE FUNCTION plpgsql_subquery_test(int, int) RETURNS TABLE(count bigint) AS $$
DECLARE
BEGIN
RETURN QUERY
SELECT
count(*)
FROM
users_table
JOIN
(SELECT
ma.user_id, (GREATEST(coalesce(ma.value_4 / 250, 0.0) + GREATEST(1.0))) / 2 AS prob
FROM
users_table AS ma, events_table as short_list
WHERE
short_list.user_id = ma.user_id and ma.value_1 < $1 and short_list.event_type < 3
) temp
ON users_table.user_id = temp.user_id
WHERE
users_table.value_1 < $2;
END;
$$ LANGUAGE plpgsql;
-- enough times (6+) to actually use prepared statements
SELECT plpgsql_subquery_test(1, 2);
SELECT plpgsql_subquery_test(1, 2);
SELECT plpgsql_subquery_test(1, 2);
SELECT plpgsql_subquery_test(1, 2);
SELECT plpgsql_subquery_test(1, 2);
SELECT plpgsql_subquery_test(1, 2);
-- this should also work, but should return 0 given that int = NULL is always returns false
SELECT plpgsql_subquery_test(1, NULL);
CREATE FUNCTION sql_subquery_test(int, int) RETURNS bigint AS $$
SELECT
count(*)
FROM
users_table
JOIN
(SELECT
ma.user_id, (GREATEST(coalesce(ma.value_4 / 250, 0.0) + GREATEST(1.0))) / 2 AS prob
FROM
users_table AS ma, events_table as short_list
WHERE
short_list.user_id = ma.user_id and ma.value_1 < $1 and short_list.event_type < 3
) temp
ON users_table.user_id = temp.user_id
WHERE
users_table.value_1 < $2;
$$ LANGUAGE SQL;
-- should error out
SELECT sql_subquery_test(1,1);
-- the joins are actually removed since they are
-- not needed by PostgreSQL planner (e.g., target list
-- doesn't contain anything from there)
-- but Citus can still pushdown this query
SELECT
t1.user_id, count(*)
FROM users_table t1
LEFT JOIN (
SELECT
user_id
FROM
users_table
UNION
SELECT
user_id
FROM
events_table
) t2 ON t1.user_id = t2.user_id
INNER JOIN (
SELECT
user_id
FROM
users_table
) t3 ON t1.user_id = t3.user_id
GROUP BY 1
ORDER BY 2 DESC;
-- the joins are actually removed since they are
-- not needed by PostgreSQL planner (e.g., target list
-- doesn't contain anything from there)
-- but Citus can still plan this query even though the query
-- is not safe to pushdown
SELECT
t1.user_id, count(*)
FROM users_table t1
LEFT JOIN (
SELECT
user_id
FROM
users_table
UNION
SELECT
value_2
FROM
events_table
) t2 ON t1.user_id = t2.user_id
INNER JOIN (
SELECT
user_id
FROM
users_table
) t3 ON t1.user_id = t3.user_id
GROUP BY 1
ORDER BY 2 DESC;
-- Similar to the above queries, but
-- this time the joins are not removed because
-- target list contains all the entries
SELECT
*
FROM users_table t1
LEFT JOIN (
SELECT
user_id
FROM
users_table
UNION
SELECT
user_id
FROM
events_table
) t2 ON t1.user_id = t2.user_id
INNER JOIN (
SELECT
user_id
FROM
users_table
) t3 ON t1.user_id = t3.user_id
ORDER BY 1 DESC, 2 DESC, 3 DESC, 4 DESC, 5 DESC, 6 DESC, 7 DESC, 8 DESC
LIMIT 5;
DROP FUNCTION plpgsql_subquery_test(int, int);
DROP FUNCTION sql_subquery_test(int, int);