Re: Make attstattarget nullable - Mailing list pgsql-hackers

From Peter Eisentraut
Subject Re: Make attstattarget nullable
Date
Msg-id 645bc1a5-646c-4b24-9f4a-3e11bee96172@eisentraut.org
Whole thread Raw
In response to Re: Make attstattarget nullable  (Tomas Vondra <tomas.vondra@enterprisedb.com>)
Responses Re: Make attstattarget nullable
List pgsql-hackers
On 14.03.24 15:46, Tomas Vondra wrote:
>>>>> 2) The newtarget handling in AlterStatistics seems rather confusing.
>>>>> Why
>>>>> does it get set to -1 just to ignore the value later? For a while I was
>>>>> 99% sure ALTER STATISTICS ... SET STATISTICS DEFAULT will set the field
>>>>> to -1. Maybe ditching the first if block and directly checking
>>>>> stmt->stxstattarget before setting repl_val/repl_null would be better?
>>>>
>>>> But we also need to continue accepting -1 for default on input.  The
>>>> current code achieves that, the proposed variant would not.
>>>
>>> OK, I did not realize that. But then maybe this should be explained in a
>>> comment before the new "if" block, because people won't realize why it
>>> needs to be this way.
>>
>> In the new version, I tried to write this more explicitly, and updated
>> tablecmds.c to match.
> 
> WFM. It still seems a bit hard to read, but I don't know how to do it
> better. I guess it's how it has to be to deal with multiple default
> values in a backwards-compatible way. Good thing is it's localized in
> two places.

I have committed this patch series.  Thanks.




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