Обсуждение: Duplicate function call on timestamp2tm

Hi,

I find there is a duplicate function call on timestamp2tm in timestamptz_part and timestamp_part.
Is that necessary? I remove the latter one and it also works.

Best,
Japin.

Li Japin <japinli@hotmail.com> writes:
> I find there is a duplicate function call on timestamp2tm in timestamptz_part and timestamp_part.
> Is that necessary? I remove the latter one and it also works.

Huh.  I do believe you're right.  Must be an ancient copy-and-paste
mistake?

            regards, tom lane

I wrote:
> Li Japin <japinli@hotmail.com> writes:
>> I find there is a duplicate function call on timestamp2tm in timestamptz_part and timestamp_part.
>> Is that necessary? I remove the latter one and it also works.

> Huh.  I do believe you're right.  Must be an ancient copy-and-paste
> mistake?

Ah, after looking in the git history, not quite that ancient:
this duplication dates to commit 258ee1b63, which moved these
switch cases from the "if (type == RESERV)" switches in the
same functions.  In the previous coding these function calls
were actually necessary, but here they're redundant.  I guess
that's just additional ammunition for Greg's point that the
keywords were misclassified ;-).

I see from the code coverage report that we're missing coverage
for these and some other paths in timestamp[tz]_part.  Think
I'll go add some more test cases while I'm at it.

Thanks again for the report!

            regards, tom lane

Li Japin <japinli@hotmail.com> writes:
> Thanks for your confirm. Is there anything I can do?

No, I've got it.

In adding the test coverage I spoke of, I thought we should allow
the date_part tests to check all the entries in timestamp[tz]_tbl
not just those around current time, and I found an independent
problem:

          timestamp          |  isoyear  | week | isodow | dow | doy 
-----------------------------+-----------+------+--------+-----+-----
...
 Tue Feb 16 17:32:01 0097 BC |       -96 |    7 |      2 |   2 |  47
 Sat Feb 16 17:32:01 0097    |        97 |    7 |      6 |   6 |  47

that is, the ISOYEAR case is failing to correct for BC years.

We could imagine fixing this in date2isoyear() but I think it's
safer to leave that function alone and do the corrections
in timestamp[tz]_part.  Note for example that formatting.c
already applies a BC correction to the result; and I think the
usage in date2isoyearday() requires sticking to the year-zero-exists
convention, too.

            regards, tom lane