Re: proposal: row_to_array function

Hi

here is rebased patch.

It contains both patches - row_to_array function and foreach array support.

This design is in conformity with hstore functions. There can be good
synergy.

Regards

Pavel

2015-03-28 23:53 GMT+01:00 Jeff Janes <jeff(dot)janes(at)gmail(dot)com>:

> On Tue, Jan 27, 2015 at 10:58 AM, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
> wrote:
>
>> Hi
>>
>> 2015-01-27 11:41 GMT+01:00 Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>:
>>
>>>
>>>
>>> 2015-01-26 21:44 GMT+01:00 Jim Nasby <Jim(dot)Nasby(at)bluetreble(dot)com>:
>>>
>>>> On 1/25/15 4:23 AM, Pavel Stehule wrote:
>>>>
>>>>>
>>>>> I tested a concept iteration over array in format [key1, value1, key2,
>>>>> value2, .. ] - what is nice, it works for [[key1,value1],[key2, value2],
>>>>> ...] too
>>>>>
>>>>> It is only a few lines more to current code, and this change doesn't
>>>>> break a compatibility.
>>>>>
>>>>> Do you think, so this patch is acceptable?
>>>>>
>>>>> Ideas, comments?
>>>>>
>>>>
>>>> Aside from fixing the comments... I think this needs more tests on
>>>> corner cases. For example, what happens when you do
>>>>
>>>> foreach a, b, c in array(array(1,2),array(3,4)) ?
>>>>
>>>
>>> it is relative simple behave -- empty values are NULL
>>>
>>> array(1,2),array(3,4) -- do you think ARRAY[[1,2],[3,4]] is effectively
>>> ARRAY[1,2,3,4]
>>>
>>>
>>>>
>>>> Or the opposite case of
>>>>
>>>> foreach a,b in array(array(1,2,3))
>>>>
>>>> Also, what about:
>>>>
>>>> foreach a,b in '{{{1,2},{3,4}},{{5,6},{7,8}}}'::int[] ?
>>>
>>>
>>>
>>> postgres=# select array(select
>>> unnest('{{{1,2},{3,4}},{{5,6},{7,8}}}'::int[]));
>>> array
>>> -------------------
>>> {1,2,3,4,5,6,7,8}
>>> (1 row)
>>>
>>> so it generate pairs {1,2}{3,4},{5,6},{7,8}
>>>
>>
>> I fixed situation when array has not enough elements.
>>
>
>
> This no longer applies due to conflicts in src/pl/plpgsql/src/pl_exec.c
> caused by e524cbdc45ec6d677b1dd49
>
> Also, what is the relationship of this patch to the row_to_array patch?
> Are they independent, or does one depend on the other? row_to_array by
> itself applies but doesn't compile.
>
> Cheers,
>
> Jeff
>