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Re: BUG #17913: alter column set (n_distinct=...) on partition head doesn't work for declarative partitioned tables - Mailing list pgsql-bugs

From Maxim Boguk
Subject Re: BUG #17913: alter column set (n_distinct=...) on partition head doesn't work for declarative partitioned tables
Date
Msg-id CAK-MWwRfF2_EMyBdspehezBe0+TV-m1tJh-QTnW2YasKXO5uvQ@mail.gmail.com
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In response to Re: BUG #17913: alter column set (n_distinct=...) on partition head doesn't work for declarative partitioned tables  (David Rowley <dgrowleyml@gmail.com>)
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On Mon, May 1, 2023 at 2:41 PM David Rowley <dgrowleyml@gmail.com> wrote:
On Mon, 1 May 2023 at 15:03, PG Bug reporting form
<noreply@postgresql.org> wrote:
> I found that the
> alter table sometable alter somecolumn set (n_distinct=...);
> Doesn't affect distinct values estimation if sometable - declarative
> partitioned table.

It might not be that intuitive, but n_distinct_inherited is the option for that.

Maybe the documentation [1] should mention partition partitions as
well as "inheritance children" is this isn't clear.

David

[1] https://www.postgresql.org/docs/current/sql-altertable.html


Thank you very much, I don't know how I missed this moment in documentation.


--
Maxim Boguk
Senior Postgresql DBA
https://dataegret.com/

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