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

On Wednesday, May 26, 2021, 德哥 <digoal(at)126(dot)com> wrote:

>
> The generated column can be used to automatically generate the modified
> timestamp of a tuple, but PG 12 currently supports this scenario. PG 13 has
> started to change its behavior, which makes our application need to be
> modified. This is the first time I have ever seen a PG upgrade kill a nice
> feature.
>
>
>
It was never a feature in the first place so nothing has been killed. The
documentation says the function must be immutable. Your function is not.
You should have used a trigger, and the fact you had to write a wrapper
function to hack the volatility means that, frankly, its your disregard for
a known limitation that has produced this need to change your application
with the release of a new major version - not any bug or decision on the
part of PostgreSQL.

David J.