Re: [PATCH] GROUP BY ALL

Hi

st 24. 7. 2024 v 10:57 odesílatel Jelte Fennema-Nio <postgres(at)jeltef(dot)nl>
napsal:

> On Mon, 22 Jul 2024 at 22:55, David Christensen <david(at)pgguru(dot)net> wrote:
> > I see that there'd been some chatter but not a lot of discussion about
> > a GROUP BY ALL feature/functionality. There certainly is utility in
> > such a construct IMHO.
>
> +1 from me. When exploring data, this is extremely useful because you
> don't have to update the GROUP BY clause every time
>
> Regarding the arguments against this:
> 1. I don't think this is any more unreadable than being able to GROUP
> BY 1, 2, 3. Or being able to use column aliases from the SELECT in the
> GROUP BY clause. Again this is already allowed. Personally I actually
> think it's more readable than specifying e.g. 5 columns in the group
> by, because then I have to cross-reference with columns in the SELECT
> clause to find out if they are the same. With ALL I instantly know
> it's grouped by all
> 2. This is indeed not part of the standard. But we have many things
> that are not part of the standard. I think as long as we use the same
> syntax as snowflake, databricks and duckdb I personally don't see a
> big problem. Then we could try and make this be part of the standard
> in the next version of the standard.
>

Aggregation against more columns is pretty slow and memory expensive in
Postgres.

DuckDB is an analytic database with different storage, different executors.
I like it very much, but I am not sure if I want to see these features in
Postgres.

Lot of developers are not very smart, and with proposed feature, then
instead to write correct and effective query, then they use just GROUP BY
ALL. Slow query should look like a slow query :-)

Regards

Pavel