Re:Re: BUG #17036: generated column cann't modifyed auto when update

在 2021-05-27 10:33:40，"David G. Johnston" <david.g.johnston@gmail.com> 写道：

On Wednesday, May 26, 2021, 德哥 <digoal@126.com> wrote:

And immutable function is stable when parameter not change, when parameter changed , the immutable function will recall and recompute.

but in PG 13 and PG 14 , it is also wrong.

```

create or replace function im_now (anyelement) returns timestamptz as $$  

  select now();  

$$ language sql strict immutable; 

create table t1 (id int primary key, c1 int, info text, crt_time timestamp, 

mod_time timestamp GENERATED ALWAYS AS (im_now(t1)) stored); 

 

This seems to be related to this already reported bug (the similar one I noted in my other reply).

https://www.postgresql.org/message-id/CAM_DEiWR2DPT6U4xb-Ehigozzd3n3G37ZB1%2B867zbsEVtYoJww%40mail.gmail.com

David J.