Re: minor fix for acquire_inherited_sample_rows - Mailing list pgsql-hackers

From Amit Langote
Subject Re: minor fix for acquire_inherited_sample_rows
Date
Msg-id c6347e39-ada0-4981-2549-d70ceb8c4f12@lab.ntt.co.jp
Whole thread Raw
In response to Re: minor fix for acquire_inherited_sample_rows  (Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>)
List pgsql-hackers
On 2018/04/27 22:42, Ashutosh Bapat wrote:
> On Thu, Apr 26, 2018 at 7:08 PM, Amit Langote <amitlangote09@gmail.com> wrote:
>> On Thu, Apr 26, 2018 at 9:54 PM, Ashutosh Bapat
>> <ashutosh.bapat@enterprisedb.com> wrote:
>>> On Thu, Apr 26, 2018 at 1:08 AM, Robert Haas <robertmhaas@gmail.com> wrote:
>>>> +1.  I think we're really abusing equalTupleDescs() for purposes for
>>>> which it was not invented.  Instead of changing it, let's invent a new
>>>> function that tests for the thing partitioning cares about (same
>>>> ordering of the same columns with the same type information) and call
>>>> it logicallyEqualTupleDescs() or something like that.
>>>
>>> Why don't we just rely on the output of convert_tuples_by_name(),
>>> which it seems is always called right now? What's advantage of adding
>>> another tuple descriptor comparison?
>>
>> The patch I mentioned in my email above does more or less that (what
>> you're saying we should do).  In fact it even modifies
>> convert_tuple_by_name and convert_tuple_by_name_map to remove some
>> redundant computation.  See that patch here if you're interested:
>>
>> https://www.postgresql.org/message-id/825031be-942c-8c24-6163-13c27f217a3d%40lab.ntt.co.jp
> 
> I spent some time looking at the patch. The patch clubs all kinds of
> refactoring together, making review a bit difficult. I think, it would
> be better to split the patch into multiple, each addressing one set of
> changes, it might become easier to review.

Thanks Ashutosh for looking at it.  I will think of a way to break it up
when I re-propose it for the next cycle.

Regards,
Amit



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