--
-- MULTI_SUBQUERY
--
-- Create tables for subquery tests
CREATE TABLE lineitem_subquery (
	l_orderkey bigint not null,
	l_partkey integer not null,
	l_suppkey integer not null,
	l_linenumber integer not null,
	l_quantity decimal(15, 2) not null,
	l_extendedprice decimal(15, 2) not null,
	l_discount decimal(15, 2) not null,
	l_tax decimal(15, 2) not null,
	l_returnflag char(1) not null,
	l_linestatus char(1) not null,
	l_shipdate date not null,
	l_commitdate date not null,
	l_receiptdate date not null,
	l_shipinstruct char(25) not null,
	l_shipmode char(10) not null,
	l_comment varchar(44) not null,
	PRIMARY KEY(l_orderkey, l_linenumber) );
SELECT master_create_distributed_table('lineitem_subquery', 'l_orderkey', 'range');
 master_create_distributed_table 
---------------------------------
 
(1 row)

CREATE TABLE orders_subquery (
	o_orderkey bigint not null,
	o_custkey integer not null,
	o_orderstatus char(1) not null,
	o_totalprice decimal(15,2) not null,
	o_orderdate date not null,
	o_orderpriority char(15) not null,
	o_clerk char(15) not null,
	o_shippriority integer not null,
	o_comment varchar(79) not null,
	PRIMARY KEY(o_orderkey) );
SELECT master_create_distributed_table('orders_subquery', 'o_orderkey', 'range');
 master_create_distributed_table 
---------------------------------
 
(1 row)

SET citus.task_executor_type TO 'task-tracker';
-- Check that we don't allow subquery pushdown in default settings.
SELECT
	avg(unit_price)
FROM
	(SELECT
		l_orderkey,
		avg(o_totalprice) AS unit_price
	FROM
		lineitem_subquery,
		orders_subquery
	WHERE
		l_orderkey = o_orderkey
	GROUP BY
		l_orderkey) AS unit_prices;
ERROR:  cannot perform distributed planning on this query
DETAIL:  Join in subqueries is not supported yet
SET citus.subquery_pushdown to TRUE;
-- Check that we don't crash if there are not any shards.
SELECT
	avg(unit_price)
FROM
	(SELECT
		l_orderkey,
		avg(o_totalprice) AS unit_price
	FROM
		lineitem_subquery,
		orders_subquery
	WHERE
		l_orderkey = o_orderkey
	GROUP BY
		l_orderkey) AS unit_prices;
 avg 
-----
    
(1 row)

-- Stage data to tables.
SET citus.shard_max_size TO "1MB";
\STAGE lineitem_subquery FROM '@abs_srcdir@/data/lineitem.1.data' with delimiter '|'
\STAGE lineitem_subquery FROM '@abs_srcdir@/data/lineitem.2.data' with delimiter '|'
\STAGE orders_subquery FROM '@abs_srcdir@/data/orders.1.data' with delimiter '|'
\STAGE orders_subquery FROM '@abs_srcdir@/data/orders.2.data' with delimiter '|'
-- Check that we error out if shard min/max values are not exactly same.
SELECT
	avg(unit_price)
FROM
	(SELECT
		l_orderkey,
		avg(o_totalprice) AS unit_price
	FROM
		lineitem_subquery,
		orders_subquery
	WHERE
		l_orderkey = o_orderkey
	GROUP BY
		l_orderkey) AS unit_prices;
ERROR:  cannot push down this subquery
DETAIL:  Shards of relations in subquery need to have 1-to-1 shard partitioning
-- Update metadata in order to make all shards equal.
UPDATE pg_dist_shard SET shardmaxvalue = '14947' WHERE shardid = 102024;
-- If group by is not on partition column then we error out.
SELECT
	avg(order_count)
FROM
	(SELECT
		l_suppkey,
		count(*) AS order_count
	FROM
		lineitem_subquery
	GROUP BY
		l_suppkey) AS order_counts;
ERROR:  cannot push down this subquery
DETAIL:  Group by list without partition column is currently unsupported
-- Check that we error out if join is not on partition columns.
SELECT
	avg(unit_price)
FROM
	(SELECT
		l_orderkey,
		avg(o_totalprice / l_quantity) AS unit_price
	FROM
		lineitem_subquery,
		orders_subquery
	GROUP BY
		l_orderkey) AS unit_prices;
ERROR:  cannot push down this subquery
DETAIL:  Relations need to be joining on partition columns
SELECT
	avg(unit_price)
FROM
	(SELECT
		l_orderkey,
		avg(o_totalprice / l_quantity) AS unit_price
	FROM
		lineitem_subquery,
		orders_subquery
	WHERE
		l_orderkey = o_custkey
	GROUP BY
		l_orderkey) AS unit_prices;
ERROR:  cannot push down this subquery
DETAIL:  Relations need to be joining on partition columns
-- Check that we error out if there is union all.
SELECT count(*) FROM
(
   (SELECT l_orderkey FROM lineitem_subquery) UNION ALL
   (SELECT 1::bigint)
) b;
ERROR:  cannot perform distributed planning on this query
DETAIL:  Complex table expressions are currently unsupported
-- Check that we error out if queries in union do not include partition columns.
SELECT count(*) FROM
(
   (SELECT l_orderkey FROM lineitem_subquery) UNION
   (SELECT l_partkey FROM lineitem_subquery)
) b;
ERROR:  cannot push down this subquery
DETAIL:  Union clauses need to select partition columns
-- Check that we run union queries if partition column is selected.
SELECT count(*) FROM
(
   (SELECT l_orderkey FROM lineitem_subquery) UNION
   (SELECT l_orderkey FROM lineitem_subquery)
) b;
 count 
-------
  2985
(1 row)

-- Check that we error out if the outermost query has subquery join.
SELECT
	avg(o_totalprice/l_quantity)
FROM
		(SELECT
			l_orderkey,
			l_quantity
		FROM
			lineitem_subquery
		ORDER BY
			l_quantity
		LIMIT 10
		) lineitem_quantities
	JOIN LATERAL
		(SELECT
			o_totalprice
		FROM
			orders_subquery
		WHERE
			lineitem_quantities.l_orderkey = o_orderkey) orders_price ON true;
ERROR:  cannot perform distributed planning on this query
DETAIL:  Join in subqueries is not supported yet
-- Check that we error out if the outermost query is a distinct clause.
SELECT
	count(DISTINCT a)
FROM (
	SELECT
		count(*) a
	FROM
		lineitem_subquery
) z;
ERROR:  cannot push down this subquery
DETAIL:  distinct in the outermost query is unsupported
-- Check supported subquery types.
SELECT
	o_custkey,
	sum(order_count) as total_order_count
FROM
	(SELECT
		o_orderkey,
		o_custkey,
		count(*) AS order_count
	FROM
		orders_subquery
	WHERE
		o_orderkey > 0 AND
		o_orderkey < 12000
	GROUP BY
		o_orderkey, o_custkey) AS order_counts
GROUP BY
	o_custkey
ORDER BY
	total_order_count DESC,
	o_custkey ASC
LIMIT 10;
 o_custkey | total_order_count 
-----------+-------------------
      1462 |                 9
       619 |                 8
       643 |                 8
      1030 |                 8
      1486 |                 8
        79 |                 7
       304 |                 7
       319 |                 7
       343 |                 7
       448 |                 7
(10 rows)

SELECT
	avg(unit_price)
FROM
	(SELECT
		l_orderkey,
		avg(o_totalprice / l_quantity) AS unit_price
	FROM
		lineitem_subquery,
		orders_subquery
	WHERE
		l_orderkey = o_orderkey
	GROUP BY
		l_orderkey) AS unit_prices
WHERE
	unit_price > 1000 AND
	unit_price < 10000;
          avg          
-----------------------
 4968.2889885208475549
(1 row)

-- Check that if subquery is pulled, we don't error and run query properly.
SELECT count(*) FROM
(
	SELECT l_orderkey FROM (
		(SELECT l_orderkey FROM lineitem_subquery) UNION
		(SELECT l_orderkey FROM lineitem_subquery)
	) a
	WHERE l_orderkey = 1
) b;
 count 
-------
     1
(1 row)

SELECT count(*) FROM
(
	SELECT * FROM (
		(SELECT * FROM lineitem_subquery) UNION
		(SELECT * FROM lineitem_subquery)
	) a
	WHERE l_orderkey = 1
) b;
 count 
-------
     6
(1 row)

SELECT max(l_orderkey) FROM
(
	SELECT l_orderkey FROM (
		SELECT
			l_orderkey
		FROM
			lineitem_subquery
		WHERE
			l_orderkey < 20000
		GROUP BY
			l_orderkey
  ) z
) y;
  max  
-------
 14947
(1 row)

-- Load more data to one relation, then test if we error out because of different
-- shard counts for joining relations.
\STAGE orders_subquery FROM '@abs_srcdir@/data/orders.1.data' with delimiter '|'
SELECT
	avg(unit_price)
FROM
	(SELECT
		l_orderkey,
		avg(o_totalprice / l_quantity) AS unit_price
	FROM
		lineitem_subquery,
		orders_subquery
	WHERE
		l_orderkey = o_orderkey
	GROUP BY
		l_orderkey) AS unit_prices;
ERROR:  cannot push down this subquery
DETAIL:  Shards of relations in subquery need to have 1-to-1 shard partitioning
-- Check that we can prune shards in subqueries with VARCHAR partition columns
CREATE TABLE subquery_pruning_varchar_test_table
(
   a varchar,
   b int
);
SELECT master_create_distributed_table('subquery_pruning_varchar_test_table', 'a', 'hash');
 master_create_distributed_table 
---------------------------------
 
(1 row)

SELECT master_create_worker_shards('subquery_pruning_varchar_test_table', 4, 1);
 master_create_worker_shards 
-----------------------------
 
(1 row)

SET citus.subquery_pushdown TO TRUE;
SET client_min_messages TO DEBUG2;
SELECT * FROM 
	(SELECT count(*) FROM subquery_pruning_varchar_test_table WHERE a = 'onder' GROUP BY a) 
AS foo;
DEBUG:  predicate pruning for shardId 102029
DEBUG:  predicate pruning for shardId 102027
DEBUG:  predicate pruning for shardId 102026
 count 
-------
(0 rows)

SELECT * FROM 
	(SELECT count(*) FROM subquery_pruning_varchar_test_table WHERE 'eren' = a GROUP BY a)
AS foo;
DEBUG:  predicate pruning for shardId 102029
DEBUG:  predicate pruning for shardId 102028
DEBUG:  predicate pruning for shardId 102026
 count 
-------
(0 rows)

SET client_min_messages TO NOTICE;
-- test subquery join on VARCHAR partition column 
SELECT * FROM
	(SELECT 
		a_inner AS a
	FROM
		(SELECT 
			subquery_pruning_varchar_test_table.a AS a_inner
		FROM 
		 	subquery_pruning_varchar_test_table
		GROUP BY 
		  	subquery_pruning_varchar_test_table.a
		HAVING 
		  	count(subquery_pruning_varchar_test_table.a) < 3) 
		AS f1,
		(SELECT 
		 	subquery_pruning_varchar_test_table.a
		FROM 
		  	subquery_pruning_varchar_test_table
		GROUP BY 
		  	subquery_pruning_varchar_test_table.a
		HAVING 
		  	sum(coalesce(subquery_pruning_varchar_test_table.b,0)) > 20.0) 
		AS f2
	WHERE 
		f1.a_inner = f2.a
	GROUP BY 
		a_inner)
AS foo;
 a 
---
(0 rows)

DROP TABLE subquery_pruning_varchar_test_table;
ALTER SEQUENCE pg_catalog.pg_dist_shardid_seq RESTART 102026;