Re: [PATCH] Fix conversion for Decimal arguments in plpython functions

The v2 patch does not work for me: regression tests for plpython fail on
the plpython_types test: every numeric is converted to None.

It seems the global decimal ctor is not initialized.

Please find two patches, to be applied on top of the v2 patch: one
initializes the decimal ctor, the other uses cdecimal when possible.

Using the performance test from steve, on my machine:

- with cdecimal installed: ~84ms
- without cdecimal installed (standard decimal module): ~511ms

2013/6/26 Szymon Guz <mabewlun(at)gmail(dot)com>

> On 26 June 2013 01:40, Steve Singer <steve(at)ssinger(dot)info> wrote:
>
>> On 06/25/2013 06:42 AM, Szymon Guz wrote:
>>
>>
>>
>>> Hi,
>>>
>>> I've attached a new patch. I've fixed all the problems you've found,
>>> except for the efficiency problem, which has been described in previous
>>> email.
>>>
>>> thanks,
>>> Szymon
>>>
>>>
>> This version of the patch addresses the issues I mentioned. Thanks for
>> looking into seeing if the performance issue is with our conversions to
>> strings or inherit with the python decimal type. I guess we (Postgresql)
>> can't do much about it. A runtime switch to use cdecimal if it is
>> available is a good idea, but I agree with you that could be a different
>> patch.
>>
>> One minor thing I noticed in this round,
>>
>> PLy_elog(ERROR, "could not import module 'decimal'");
>>
>> I think should have "decimal" in double-quotes.
>>
>> I think this patch is ready for a committer to look at it.
>>
>> Steve
>>
>>
>>>
>>
> Hi Steve,
> thanks for the review.
>
> I was thinking about speeding up the Decimal conversion using the module
> you wrote about. What about trying to import it, if it fails, than trying
> to load decimal.Decimal? There will be no warning in logs, just additional
> information in documentation that it uses this module if it is available?
>
> thanks,
> Szymon
>