Re: Indexes on expressions with multiple columns and operators - Mailing list pgsql-performance

From Frédéric Yhuel
Subject Re: Indexes on expressions with multiple columns and operators
Date
Msg-id d701cab9-c7c9-44f7-ac10-d17ed78bedbb@dalibo.com
Whole thread Raw
In response to Re: Indexes on expressions with multiple columns and operators  (Andrei Lepikhov <lepihov@gmail.com>)
Responses Re: Indexes on expressions with multiple columns and operators
List pgsql-performance

On 9/23/25 12:43, Andrei Lepikhov wrote:
> But is it the same for the 'distinct' statistics? It seems you should 
> love it - the number of groups in GROUP-BY, DISTINCT, and even HashJoin 
> should be estimated more precisely, no?

I think it has more potential, and I would love to use this weapon, but 
I haven't had the opportunity yet. It would be interesting to know how 
much it is used in real life.

To get back to the topic of partitioned statistics, do you know if SQL 
Server is smart enough to handle this case [1] that we discussed last 
year? (with filtered statistics)

[1] 
https://www.postgresql.org/message-id/flat/b860c71a-7cab-4d88-ad87-8c1f2eea9ae8%40dalibo.com



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