# name: test/sql/cte/test_cte.test
# description: Test Common Table Expressions (CTE)
# group: [cte]

statement ok
PRAGMA enable_verification

statement ok
create table a(i integer);

statement ok
insert into a values (42);

query I
with cte1 as (Select i as j from a) select * from cte1;
----
42

query I
with cte1 as (Select i as j from a) select x from cte1 t1(x);
----
42

query I
with cte1(xxx) as (Select i as j from a) select xxx from cte1;
----
42

query I
with cte1(xxx) as (Select i as j from a) select x from cte1 t1(x);
----
42

query II
with cte1 as (Select i as j from a), cte2 as (select ref.j as k from cte1 as ref), cte3 as (select ref2.j+1 as i from cte1 as ref2) select * from cte2 , cte3;
----
42	43

query I
with cte1 as (select i as j from a), cte2 as (select ref.j as k from cte1 as ref), cte3 as (select ref2.j+1 as i from cte1 as ref2) select * from cte2 union all select * FROM cte3;
----
42
43

# duplicate CTE alias
statement error
with cte1 as (select 42), cte1 as (select 42) select * FROM cte1;
----


# multiple uses of same CTE
query II
with cte1 as (Select i as j from a) select * from cte1 cte11, cte1 cte12;
----
42	42

# refer to CTE in subquery
query I
with cte1 as (Select i as j from a) select * from cte1 where j = (select max(j) from cte1 as cte2);
----
42

# multi-column name alias
query II
with cte1(x, y) as (select 42 a, 84 b) select zzz, y from cte1 t1(zzz);
----
42	84

# use a CTE in a view definition
statement ok
create view va AS (with cte as (Select i as j from a) select * from cte);

query I
select * from va
----
42

# nested CTE views that re-use CTE aliases
query I
with cte AS (SELECT * FROM va) SELECT * FROM cte;
----
42

# multiple ctes in a view definition
statement ok
create view vb AS (with cte1 as (Select i as j from a), cte2 as (select ref.j+1 as k from cte1 as ref) select * from cte2);

query I
select * from vb
----
43

# cte in set operation node
query I
SELECT 1 UNION ALL (WITH cte AS (SELECT 42) SELECT * FROM cte);
----
1
42

# cte in nested set operation node
query I
SELECT 1 UNION ALL (WITH cte AS (SELECT 42) SELECT * FROM cte UNION ALL SELECT * FROM cte);
----
1
42
42

# cte in recursive cte
query I
WITH RECURSIVE cte(d) AS (
		SELECT 1
	UNION ALL
		(WITH c(d) AS (SELECT * FROM cte)
			SELECT d + 1
			FROM c
			WHERE FALSE
		)
)
SELECT max(d) FROM cte;
----
1

# test CTE with nested aliases in where clause
query II
with cte (a) as (
    select 1
)
select
    a as alias1,
    alias1 as alias2
from cte
where alias2 > 0;
----
1	1

# recursive CTE and a non-recursive CTE with except
query I
WITH RECURSIVE t AS (
  SELECT 1 AS a
    UNION ALL
  SELECT a+1
  FROM t
  WHERE a < 10
), s AS (
  (VALUES (5), (6), (7), (8), (9), (10), (11), (12), (13), (42))
  EXCEPT
  TABLE t
)
SELECT * FROM s AS _(x) ORDER BY x;
----
11
12
13
42

# recursive CTE with except in recursive part (but not as a recursive anchor)
query I
WITH RECURSIVE t AS (
  select 1 as a
  union all
  (select a+1
  from t
  where a < 10
  	except
  SELECT 4)
), s AS (
  (values (5), (6), (7))
  except
  table t
)
SELECT * FROM s AS _(x) ORDER BY x;
----
5
6
7

query I
WITH RECURSIVE
  t(b) AS MATERIALIZED (
    (WITH helper(c) AS (
      SELECT 5
    ), h1 AS
    (SELECT * FROM helper h
    UNION
    SELECT 7 FROM helper h)
    SELECT * FROM h1)
  )
SELECT * FROM t ORDER BY b;
----
5
7

require no_alternative_verify

# FIXME: this one should work with ALTERNATIVE_VERIFY, but doesn't yet
# something wrong with binding a CTE inside a recursive CTE
query I
WITH RECURSIVE
  t(b) AS MATERIALIZED (
    (WITH helper(c) AS (
      SELECT 5
    )
    SELECT * FROM helper h
    UNION
    SELECT 7
    )
  )
SELECT * FROM t ORDER BY b;
----
5
7

# reference to CTE before its actually defined, can't with ALTERNATIVE_VERIFY because everything gets materialized
statement error
with cte3 as (select ref2.j as i from cte1 as ref2), cte1 as (Select i as j from a), cte2 as (select ref.j+1 as k from cte1 as ref) select * from cte2 union all select * FROM cte3;
----
Catalog Error: Table with name cte1 does not exist!

statement error
WITH t(x) AS (SELECT x)
SELECT *
FROM  range(10) AS _(x), LATERAL (SELECT * FROM t);
----

statement error
WITH cte AS (SELECT x)
SELECT b.x
FROM (SELECT 1) _(x), LATERAL (SELECT * FROM cte) b(x)
----

query III
WITH RECURSIVE rec(a, b, c) AS (select a,b,c from (values(1,2,3),(1,2,3)) s(a,b,c) union select 1,2,3) select * from rec;
----
1	2	3