Re: Issues with generate_series using integer boundaries

On 3 February 2011 13:32, Thom Brown <thom@linux.com> wrote:
> Actually, further testing indicates this causes other problems:
>
> postgres=# SELECT x FROM generate_series(1, 9,-1) AS a(x);
>  x
> ---
>  1
> (1 row)
>
> Should return no rows.
>
> postgres=# SELECT x FROM generate_series(1, 9,3) AS a(x);
>  x
> ----
>  1
>  4
>  7
>  10
> (4 rows)
>
> Should return 3 rows.

Still messy code, but the attached patch does the job now:

postgres=# SELECT x FROM
generate_series(2147483643::int4,2147483647::int4) AS a(x);
     x
------------
 2147483643
 2147483644
 2147483645
 2147483646
 2147483647
(5 rows)

postgres=# SELECT x FROM
generate_series(2147483642::int4,2147483647::int4, 2) AS a(x);
     x
------------
 2147483642
 2147483644
 2147483646
(3 rows)

postgres=# SELECT x FROM
generate_series(2147483643::int4,2147483647::int4, 6) AS a(x);
     x
------------
 2147483643
(1 row)

postgres=# SELECT x FROM generate_series((-2147483643)::int4,
(-2147483648)::int4, -1) AS a(x);
      x
-------------
 -2147483643
 -2147483644
 -2147483645
 -2147483646
 -2147483647
 -2147483648
(6 rows)

postgres=# SELECT x FROM generate_series(1, 9,-1) AS a(x);
 x
---
(0 rows)

postgres=# SELECT x FROM generate_series(1, 9,3) AS a(x);
 x
---
 1
 4
 7
(3 rows)

--
Thom Brown
Twitter: @darkixion
IRC (freenode): dark_ixion
Registered Linux user: #516935