| Lists: | pgsql-hackers |
|---|
| From: | ioguix(at)free(dot)fr |
|---|---|
| To: | PostgreSQL-development Hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Bug ? different behaviour between 8.3 and 8.4 won IS NULL with sub arrays of nulls |
| Date: | 2010-01-19 15:19:11 |
| Message-ID: | alpine.DEB.2.00.1001191600101.25223@xigix.ioguix.net |
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| Lists: | pgsql-hackers |
Hi,
I found a difference of behaviour between 8.3 and 8.4 on IS NULL with
multi-level arrays with NULL values.
I looked at the Changelog between 8.3 and 8.4, but I didn't find something
really clear about this.
Is this a bug or a known issue or a normal, documented,
difference of behaviour ?
See the following use case:
<~~~~~~~~~~~~~~~~~~~~~~~~
$ psql -p 5433 -U postgres -h localhost -c \
'SELECT substring(version() from 0 for 15),
ROW(NULL,NULL) IS NULL, ROW(ROW(NULL),NULL) IS NULL;'
substring | ?column? | ?column?
----------------+----------+----------
PostgreSQL 8.3 | t | f
(1 ligne)
$ psql -p 5434 -U postgres -h localhost -c \
'SELECT substring(version() from 0 for 15),
ROW(NULL,NULL) IS NULL, ROW(ROW(NULL),NULL) IS NULL;'
substring | ?column? | ?column?
----------------+----------+----------
PostgreSQL 8.4 | t | t
(1 ligne)
~~~~~~~~~~~~~~~~~~~~~~~~>
Regards,
--
Jehan-Guillaume (ioguix) de Rorthais
DBA
http://www.dalibo.com
| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | ioguix(at)free(dot)fr |
| Cc: | PostgreSQL-development Hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Bug ? different behaviour between 8.3 and 8.4 won IS NULL with sub arrays of nulls |
| Date: | 2010-01-19 16:12:56 |
| Message-ID: | 10295.1263917576@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Lists: | pgsql-hackers |
ioguix(at)free(dot)fr writes:
> I found a difference of behaviour between 8.3 and 8.4 on IS NULL with
> multi-level arrays with NULL values.
8.3's behavior is just a bug --- try comparing the results when the
values are variables that happen to be null, rather than simple
constant nulls. 8.4 is consistent with that case, 8.3 isn't.
regards, tom lane
| From: | "Jehan-Guillaume (ioguix) de Rorthais" <ioguix(at)free(dot)fr> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | PostgreSQL-development Hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Bug ? different behaviour between 8.3 and 8.4 won IS NULL with sub arrays of nulls |
| Date: | 2010-01-20 09:53:45 |
| Message-ID: | alpine.DEB.2.00.1001201037400.25223@xigix.ioguix.net |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Lists: | pgsql-hackers |
On Tue, 19 Jan 2010, Tom Lane wrote:
> ioguix(at)free(dot)fr writes:
>> I found a difference of behaviour between 8.3 and 8.4 on IS NULL with
>> multi-level arrays with NULL values.
>
> 8.3's behavior is just a bug ---
Ok, should I report through the -bugs ml for tracking purpose ? or
is it useless cause it's on -hackers andsomeone will jump on this bug to
"fix and forget it" ?
> try comparing the results when the
> values are variables that happen to be null, rather than simple
> constant nulls. 8.4 is consistent with that case, 8.3 isn't.
Right, it behaves consistently with variables.
Here is another test case where 8.3 is inconsistent with *himself* this
time:
<~~~~~~~~~~~~~~~~~~~~~~~~~~~~
postgres=# SELECT substring(version(),12,5);
substring
-----------
8.3.9
(1 ligne)
postgres=# SELECT ROW(ROW(NULL),NULL) IS NULL FROM (SELECT 1) t;
?column?
----------
t
(1 ligne)
postgres=# SELECT ROW(ROW(NULL),NULL) IS NULL;
?column?
----------
f
(1 ligne)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~>
> regards, tom lane
>
--
Jehan-Guillaume (ioguix) de Rorthais
DBA
http://www.dalibo.com