Generate range of dates using CTE Oracle - oracle

Question

I want to generate a range of days between two different dates using recursive WITH clause in Oracle.
WITH CTE_Dates (cte_date) AS
( SELECT CAST(TO_DATE('10-02-2017', 'DD-MM-YYYY') AS DATE) cte_date FROM dual
UNION ALL
SELECT CAST( (cte_date + 1) AS DATE) cte_date
FROM CTE_Dates
WHERE TRUNC(cte_date) + 1 <= TO_DATE('20-02-2017', 'DD-MM-YYYY')
)
SELECT * FROM CTE_Dates
The returned results are completely other than expected:
10-02-2017
09-02-2017
08-02-2017
07-02-2017
06-02-2017
... (unlimited)
The expected results:
10-02-2017
11-02-2017
...
19-02-2017
20-02-2017
Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production.
Edit:
As I understood, this is a known Bug in Oracle, the bug exists through Oracle 11.2.0.2 and it was fixed in 11.2.0.3.
Altarnative solution:
SELECT TRUNC (TO_DATE('10-02-2017', 'DD-MM-YYYY') + ROWNUM -1) dt
FROM DUAL
CONNECT BY ROWNUM <= (TO_DATE('20-02-2017', 'DD-MM-YYYY') - (TO_DATE('10-02-2017', 'DD-MM-YYYY')))

Answer 1

This was a known bug in recursive CTE's in Oracle 11 (specifically with regard to date arithmetic). Fixed in Oracle 12. Exactly that behavior: whether you add or subtract in your code, the engine always subtracts, it never adds.
EDIT: Actually, as Alex Poole pointed out in a Comment to the original post, the bug exists through Oracle 11.2.0.2 and it was fixed in 11.2.0.3. End edit
Alas I am not a paying customer, so I can't quote chapter and verse, but with a little bit of Googling you will find links to this (including on OTN where I was involved in a few threads discussing this and other bugs in recursive CTEs - some were fixed, some are still bugs in Oracle 12.1).
Added - here is one of those discussions: https://community.oracle.com/thread/3974408

Answer 2

Unless you really need to use the WITH clause there is another solution to get the expected result by using the CONNECT BY clause.
SELECT TO_DATE('10-02-2017', 'DD-MM-YYYY') AS date_range
FROM dual
UNION ALL
SELECT TO_DATE('10-02-2017', 'DD-MM-YYYY') + LEVEL
FROM dual
CONNECT BY LEVEL <= (TO_DATE('20-02-2017', 'DD-MM-YYYY') - TO_DATE('10-02-2017', 'DD-MM-YYYY'));

Answer 3

Maybe reverse order of the recursion solves the problem:
with cte_dates (cte_date) as (
select cast(to_date('20-02-2017', 'DD-MM-YYYY') as date) cte_date from dual
union all
select cast((cte_date - 1) as date) cte_date
from cte_dates
where cast(cte_date as date) > to_date('10-02-2017', 'DD-MM-YYYY')
)
select * from cte_dates
order by cte_date
;
2017-02-10
2017-02-11
2017-02-12
...
2017-02-18
2017-02-19
2017-02-20
Note: cast date as date needed due to yet another bug by RCTE in 11gR2
Old discussion here

Answer 4

You don't need a recursive WITH clause, you just need a table where number of rows > number of dates you want to generate :
WITH
dates
AS
(SELECT
TO_DATE('10-02-2017', 'DD-MM-YYYY') + (rownum - 1)
FROM
all_tables
WHERE 1=1
AND rownum < (TO_DATE('20-02-2017', 'DD-MM-YYYY') - TO_DATE('10-02-2017', 'DD-MM-YYYY')) + 2
)
SELECT
*
FROM
dates