Re: [patch] Have psql's \d+ indicate foreign partitions - Mailing list pgsql-hackers

From Justin Pryzby
Subject Re: [patch] Have psql's \d+ indicate foreign partitions
Date
Msg-id 20221024130323.GB16921@telsasoft.com
Whole thread Raw
In response to [patch] Have psql's \d+ indicate foreign partitions  (Ian Lawrence Barwick <barwick@gmail.com>)
Responses Re: [patch] Have psql's \d+ indicate foreign partitions  (Alvaro Herrera <alvherre@alvh.no-ip.org>)
List pgsql-hackers
On Mon, Oct 24, 2022 at 09:44:18PM +0900, Ian Lawrence Barwick wrote:
> Recently I have been working a lot with partitioned tables which contain a mix
> of local and foreign partitions, and find it would be very useful to be able to
> easily obtain an overview of which partitions are foreign and where they are
> located.

>     Partitions: parttest_10_0 FOR VALUES WITH (modulus 10, remainder 0),
>                 parttest_10_1 FOR VALUES WITH (modulus 10, remainder 1), server: "fdw_node2",

> which is much more informative, albeit a little more cluttered, but

> @@ -3445,6 +3451,10 @@ describeOneTableDetails(const char *schemaname,
>                  if (child_relkind == RELKIND_PARTITIONED_TABLE ||
>                      child_relkind == RELKIND_PARTITIONED_INDEX)
>                      appendPQExpBufferStr(&buf, ", PARTITIONED");
> +                else if (child_relkind == RELKIND_FOREIGN_TABLE && is_partitioned)
> +                    appendPQExpBuffer(&buf, ", server: \"%s\"", PQgetvalue(result, i, 4));
> +                else if (child_relkind == RELKIND_FOREIGN_TABLE && !is_partitioned)
> +                    appendPQExpBuffer(&buf, " (server: \"%s\")", PQgetvalue(result, i, 4));
>                  if (strcmp(PQgetvalue(result, i, 2), "t") == 0)
>                      appendPQExpBufferStr(&buf, " (DETACH PENDING)");
>                  if (i < tuples - 1)

To avoid the clutter that you mentioned, I suggest that this should show
that the table *is* foreign, but without the server - if you want to
know the server (or its options), you can run another \d command for
that (or run a SQL query).

That's similar to what's shown if the child is partitioned: a suffix
like ", PARTITIONED", but without show the partition strategy.

I had a patch to allow \d++, and maybe showing the foreign server would
be reasonable for that.  But the patch got closed, evidently lack of
interest.



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