Re: list of extended statistics on psql

On 1/12/21 2:57 AM, Tatsuro Yamada wrote:
> Hi Tomas,
>
> On 2021/01/09 9:01, Tomas Vondra wrote:
...>
>> While working on that, I realized that 'defined' might be a bit
>> ambiguous, I initially thought it means 'NOT NULL' (which it does not).
>> I propose to change it to 'requested' instead. Tatsuro, do you agree, or
>> do you think 'defined' is better?
>
> Regarding the status of extended stats, I think the followings:
>
>  - "defined": it shows the extended stats defined only. We can't know
>               whether it needs to analyze or not. I agree this name was
>                ambiguous. Therefore we should replace it with a more
> suitable
>               name.
>  - "requested": it shows the extended stats needs something. Of course,
>               we know it needs to ANALYZE because we can create the patch.
>               However, I feel there is a little ambiguity for DBA.
>               To solve this, it would be better to write an explanation of
>               the status in the document. For example,
>
> ======
> The column of the kind of extended stats (e. g. Ndistinct) shows some
> statuses.
> "requested" means that it needs to gather data by ANALYZE. "built" means
> ANALYZE
>  was finished, and the planner can use it. NULL means that it doesn't
> exists.
> ======
>
> What do you think? :-D
>

Yes, that seems reasonable to me. Will you provide an updated patch?

regards

--
Tomas Vondra
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