Message-ID: <e76f1635-a933-47bf-a826-045e20d5cfff@gmail.com>
Date: Tue, 25 Mar 2025 07:40:47 +0100
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Subject: Re: Add estimated hit ratio to Memoize in EXPLAIN to explain cost
 adjustment
To: David Rowley <dgrowleyml@gmail.com>
Cc: Ilia Evdokimov <ilya.evdokimov@tantorlabs.com>,
 Lukas Fittl <lukas@fittl.com>, Daniel Gustafsson <daniel@yesql.se>,
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
 Nikolay Samokhvalov <samokhvalov@gmail.com>
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 <51A15CD7-E31B-483D-B911-D0EB9F5FF952@yesql.se>
 <CAP53Pkz-sK8En2c05rJDcV7pz8+OsbNqOnm_SO4tsuwm=n=3OQ@mail.gmail.com>
 <bea2a2ae-3a95-4740-8926-837bacc7bd4e@tantorlabs.com>
 <CAApHDvpq2gOt3gnzkd4Ud=wrT7YRGrF3zb29jgWzDsYEhETrOA@mail.gmail.com>
 <44229379-3901-4cb0-8812-b354ef70d5e2@gmail.com>
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 <8e12aa55-39eb-4e03-a8f7-077fe02309c3@gmail.com>
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From: Andrei Lepikhov <lepihov@gmail.com>
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On 24/3/2025 23:05, David Rowley wrote:
> On Tue, 25 Mar 2025 at 10:23, Andrei Lepikhov <lepihov@gmail.com> wrote:
>>
>> On 3/23/25 22:16, David Rowley wrote:
>>> Once again, I'm not necessarily objecting to hit and evict ratios
>>> being shown, I just want to know they're actually useful enough to
>>> show and don't just bloat the EXPLAIN output needlessly. So far your
>>> arguments aren't convincing me that they are.
> 
>> I'm -1 for this redundancy.
> 
> I'm not following what the -1 is for. Is it for showing both hit and
> evict ratios?  And your vote is only for adding hit ratio?
Oh, pardon me. I wanted to say that IMO, the couple (capacity, distinct 
lookup keys) makes redundant (hit ratio, eviction ratio) and vice versa.

-- 
regards, Andrei Lepikhov