Re: Allow to collect statistics on virtual generated columns - Mailing list pgsql-hackers

From Dean Rasheed
Subject Re: Allow to collect statistics on virtual generated columns
Date
Msg-id CAEZATCUR5B=6M7H2bwRU0_6FrbSE8yHe_+9bTbRUdU=jE33yog@mail.gmail.com
Whole thread
In response to Re: Allow to collect statistics on virtual generated columns  (Yugo Nagata <nagata@sraoss.co.jp>)
Responses Re: Allow to collect statistics on virtual generated columns
Re: Allow to collect statistics on virtual generated columns
List pgsql-hackers
On Tue, 24 Mar 2026 at 10:57, Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> One concern is that CREATE STATISTICS does not allow creating extended
> statistics on a single colmun. If we try this, it raises the following error:
>
>  ERROR:  extended statistics require at least 2 columns
>
> Therefore, if we take this approach, we would need to add an exception
> to this rule for virtual columns.

I think that would be fine. It makes sense because a virtual column
expands to an expression, and we already allow CREATE STATISTICS on a
single expression.

Regards,
Dean



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