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Date: Mon, 29 Jul 2024 16:59:07 +0200
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Subject: Re: Virtual generated columns
To: jian he <jian.universality@gmail.com>
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From: Peter Eisentraut <peter@eisentraut.org>
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On 22.07.24 12:53, jian he wrote:
> another bug?
> drop table gtest12v;
> CREATE TABLE gtest12v (a int PRIMARY KEY, b bigint, c int GENERATED
> ALWAYS AS (b * 2) VIRTUAL);
> insert into gtest12v (a,b) values (11,  22147483647);
> table gtest12v;
> 
> insert ok, but select error:
> ERROR:  integer out of range
> 
> should insert fail?

I think this is the correct behavior.

There has been a previous discussion: 
https://www.postgresql.org/message-id/2e3d5147-16f8-af0f-00ab-4c72cafc896f%402ndquadrant.com

> CREATE TABLE gtest12v (a int PRIMARY KEY, b bigint, c int GENERATED
> ALWAYS AS (b * 2) VIRTUAL);
> CREATE SEQUENCE sequence_testx OWNED BY gtest12v.c;
> 
> seems to work. But I am not sure if there are any corner cases that
> make it not work.
> just want to raise this issue.

I don't think this matters.  You can make a sequence owned by any 
column, even if that column doesn't have a default that invokes the 
sequence.  So nonsensical setups are possible, but they are harmless.