Re: Is it useful to record whether plans are generic or custom?

Horiguchi-san,

On 2020/12/04 15:37, Kyotaro Horiguchi wrote:
>> And I'm also struggling with the following.
>>
>> | However, I also began to wonder how effective it would be to just
>> | distinguish between generic and custom plans. Custom plans can
>> | include all sorts of plans. and thinking cache validation, generic
>> | plans can also include various plans.
>>
>> | Considering this, I'm starting to feel that it would be better to
>> | not just keeping whether generic or cutom but the plan itself as
>> | discussed in the below thread.
>
> FWIW, that seems to me to be like some existing extension modules,
> pg_stat_plans or pg_store_plans.. The former is faster but may lose
> plans, the latter doesn't lose plans but slower. I feel that we'd
> beter consider simpler feature if we are intendeng it to be a part of
> a contrib module,

There is also pg_show_plans.
Ideally, it would be better to able to track all of the plan changes by
checking something view since Plan Stability is important for DBA when
they use PostgreSQL in Mission-critical systems.
I prefer that the feature will be released as a contrib module. :-D

Regards,
Tatsuro Yamada