Thread

Re: Use merge-based matching for MCVs in eqjoinsel

Ilia Evdokimov <ilya.evdokimov@tantorlabs.com> — 2025-10-30T10:07:22Z

Hi David,

On 27.10.2025 18:50, David Geier wrote:
> Hi Ilia!
>
> On 10.09.2025 15:56, Ilia Evdokimov wrote:
>> LGTM. Yes, I'll test this patch.
>>
>>
>>
>> Unfortunately, the JOB benchmark does not contain semi join nodes.
>> However, TPC-DS does. I'll look for the queries with slowest planner
>> times there and check them.
>>
>> I'll need some time to check both join and semi join cases with small
>> and large default_statistics_target. I'll share the results later.
>>
> Have you had a chance to test above things?

Yes, I wrote about this here: 
https://www.postgresql.org/message-id/c3dbf2ab-d72d-4033-822a-60ad8023f499%40tantorlabs.com

--
Best regards,
Ilia Evdokimov,
Tantor Labs LLC,
https://tantorlabs.com/