-- aliasing, from:
-- https://github.com/duckdb/duckdb/blob/9196dd9b0a163e6c8aada26218803d04be30c562/test/sql/subquery/table/test_aliasing.test
CREATE TABLE a(ts TIMESTAMP TIME INDEX, i INTEGER);

Affected Rows: 0

insert into a values (1, 42);

Affected Rows: 1

SELECT * FROM (SELECT i AS j FROM a GROUP BY j) WHERE j = 42;

+----+
| j  |
+----+
| 42 |
+----+

SELECT * FROM (SELECT i AS j FROM a GROUP BY i) WHERE j = 42;

+----+
| j  |
+----+
| 42 |
+----+

DROP TABLE a;

Affected Rows: 0

-- nested table subquery, from:
-- https://github.com/duckdb/duckdb/blob/2e4e2913266ddc46c7281d1b992228cb0095954b/test/sql/subquery/table/test_nested_table_subquery.test_slow
CREATE TABLE test (ts TIMESTAMP TIME INDEX, i INTEGER, j INTEGER);

Affected Rows: 0

INSERT INTO test VALUES (0, 3, 4), (1, 4, 5), (2, 5, 6);

Affected Rows: 3

SELECT * FROM (SELECT i, j FROM (SELECT j AS i, i AS j FROM (SELECT j AS i, i AS j FROM test) AS a) AS a) AS a, (SELECT i+1 AS r,j FROM test) AS b, test WHERE a.i=b.r AND test.j=a.i ORDER BY 1;

+---+---+---+---+-------------------------+---+---+
| i | j | r | j | ts                      | i | j |
+---+---+---+---+-------------------------+---+---+
| 4 | 5 | 4 | 4 | 1970-01-01T00:00:00     | 3 | 4 |
| 5 | 6 | 5 | 5 | 1970-01-01T00:00:00.001 | 4 | 5 |
+---+---+---+---+-------------------------+---+---+

SELECT i FROM (SELECT i + 1 AS i FROM (SELECT i + 1 AS i FROM (SELECT i + 1 AS i FROM test)));

+---+
| i |
+---+
| 6 |
| 7 |
| 8 |
+---+

DROP TABLE test;

Affected Rows: 0

-- subquery union, from:
-- https://github.com/duckdb/duckdb/blob/9196dd9b0a163e6c8aada26218803d04be30c562/test/sql/subquery/table/test_subquery_union.test
SELECT * FROM (SELECT 42) UNION ALL SELECT * FROM (SELECT 43) ORDER BY 1;

+-----------+
| Int64(42) |
+-----------+
| 42        |
| 43        |
+-----------+

-- table subquery, from:
-- https://github.com/duckdb/duckdb/blob/8704c7d0807d6ce1e2ebcdf6398e1b6cc050e507/test/sql/subquery/table/test_table_subquery.test
CREATE TABLE test (ts TIMESTAMP TIME INDEX, i INTEGER, j INTEGER);

Affected Rows: 0

INSERT INTO test VALUES (0, 3, 4), (1, 4, 5), (2, 5, 6);

Affected Rows: 3

SELECT * FROM (SELECT i, j AS d FROM test ORDER BY i) AS b;

+---+---+
| i | d |
+---+---+
| 3 | 4 |
| 4 | 5 |
| 5 | 6 |
+---+---+

SELECT b.d FROM (SELECT i * 2 + j AS d FROM test) AS b;

+----+
| d  |
+----+
| 10 |
| 13 |
| 16 |
+----+

SELECT a.i,a.j,b.r,b.j FROM (SELECT i, j FROM test) AS a INNER JOIN (SELECT i+1 AS r,j FROM test) AS b ON a.i=b.r ORDER BY 1;

+---+---+---+---+
| i | j | r | j |
+---+---+---+---+
| 4 | 5 | 4 | 4 |
| 5 | 6 | 5 | 5 |
+---+---+---+---+

SELECT * FROM (SELECT i, j FROM test) AS a, (SELECT i+1 AS r,j FROM test) AS b, test WHERE a.i=b.r AND test.j=a.i ORDER BY 1;

+---+---+---+---+-------------------------+---+---+
| i | j | r | j | ts                      | i | j |
+---+---+---+---+-------------------------+---+---+
| 4 | 5 | 4 | 4 | 1970-01-01T00:00:00     | 3 | 4 |
| 5 | 6 | 5 | 5 | 1970-01-01T00:00:00.001 | 4 | 5 |
+---+---+---+---+-------------------------+---+---+

SELECT sum(x) FROM (SELECT i AS x FROM test GROUP BY i) sq;

+-----------+
| sum(sq.x) |
+-----------+
| 12        |
+-----------+

SELECT sum(x) FROM (SELECT i+1 AS x FROM test GROUP BY x) sq;

+-----------+
| sum(sq.x) |
+-----------+
| 15        |
+-----------+

DROP TABLE test;

Affected Rows: 0

-- test unamed subquery, from:
-- https://github.com/duckdb/duckdb/blob/00a605270719941ca0412ad5d0a14b1bdfbf9eb5/test/sql/subquery/table/test_unnamed_subquery.test
SELECT a FROM (SELECT 42 a);

+----+
| a  |
+----+
| 42 |
+----+

SELECT * FROM (SELECT 42 a), (SELECT 43 b);

+----+----+
| a  | b  |
+----+----+
| 42 | 43 |
+----+----+

SELECT * FROM (VALUES (42, 43));

+---------+---------+
| column1 | column2 |
+---------+---------+
| 42      | 43      |
+---------+---------+

SELECT * FROM (SELECT 42 a), (SELECT 43 b), (SELECT 44 c), (SELECT 45 d);

+----+----+----+----+
| a  | b  | c  | d  |
+----+----+----+----+
| 42 | 43 | 44 | 45 |
+----+----+----+----+

SELECT * FROM (SELECT * FROM (SELECT 42 a), (SELECT 43 b)) JOIN (SELECT 44 c) ON (true) JOIN (SELECT 45 d) ON (true);

+----+----+----+----+
| a  | b  | c  | d  |
+----+----+----+----+
| 42 | 43 | 44 | 45 |
+----+----+----+----+