Re: list of extended statistics on psql

Hi,

On 2021/01/08 0:56, Tomas Vondra wrote:
> On 1/7/21 3:47 PM, Alvaro Herrera wrote:
>> On 2021-Jan-07, Tomas Vondra wrote:
>>
>>> On 1/7/21 1:46 AM, Tatsuro Yamada wrote:
>>
>>>> I overlooked the check for MCV in the logic building query
>>>> because I created the patch as a new feature on PG14.
>>>> I'm not sure whether we should do back patch or not. However, I'll
>>>> add the check on the next patch because it is useful if you decide to
>>>> do the back patch on PG10, 11, 12, and 13.
>>>
>>> BTW perhaps a quick look at the other \d commands would show if there are
>>> precedents. I didn't have time for that.
>>
>> Yes, we do promise that new psql works with older servers.
>>
>
> Yeah, makes sense. That means we need add the check for 12 / MCV.

Ah, I got it.
I fixed the patch to work with older servers to add the checking versions. And I tested \dX command on older servers (PG10 - 13).
These results look fine.

0001:
Added the check code to handle pre-PG12. It has not MCV and
pg_statistic_ext_data.
0002:
This patch is the same as the previous patch (not changed).

Please find the attached files.

>> I wonder the column names added by \dX+ is fine? For example,
>> "Ndistinct_size" and "Dependencies_size". It looks like long names,
>> but acceptable?
>>
>
> Seems acceptable - I don't have a better idea.

I see, thanks!

Thanks,
Tatsuro Yamada