Re: PL/Python adding support for multi-dimensional arrays

On 27 September 2016 at 14:58, Heikki Linnakangas <hlinnaka(at)iki(dot)fi> wrote:

> On 09/27/2016 02:04 PM, Dave Cramer wrote:
>
>> On 26 September 2016 at 14:52, Dave Cramer <pg(at)fastcrypt(dot)com> wrote:
>>
>>> This crashes with arrays with non-default lower bounds:
>>>>
>>>> postgres=# SELECT * FROM test_type_conversion_array_int
>>>> 4('[2:4]={1,2,3}');
>>>> INFO: ([1, 2, <NULL>], <type 'list'>)
>>>> server closed the connection unexpectedly
>>>> This probably means the server terminated abnormally
>>>> before or while processing the request.
>>>>
>>>> Attached patch fixes this bug, and adds a test for it.
>>>>
>>>
> I spent some more time massaging this:
>
> * Changed the loops from iterative to recursive style. I think this indeed
> is slightly easier to understand.
>
> * Fixed another segfault, with too deeply nested lists:
>
> CREATE or replace FUNCTION test_type_conversion_mdarray_toodeep() RETURNS
> int[] AS $$
> return [[[[[[[[[[[[[[[[[[1]]]]]]]]]]]]]]]]]]
> $$ LANGUAGE plpythonu;
>
> * Also, in PLySequence_ToArray(), we must check that the 'len' of the
> array doesn't overflow.
>
> * Fixed reference leak in the loop in PLySequence_ToArray() to count the
> number of dimensions.
>
> I'd like to see some updates to the docs for this. The manual doesn't
>>>> currently say anything about multi-dimensional arrays in pl/python, but
>>>> it
>>>> should've mentioned that they're not supported. Now that it is
>>>> supported,
>>>> should mention that, and explain briefly that a multi-dimensional array
>>>> is
>>>> mapped to a python list of lists.
>>>>
>>>> If the code passes I'll fix the docs
>>>
>>
> Please do, thanks!
>
>
see attached

Dave Cramer

davec(at)postgresintl(dot)com
www.postgresintl.com