Re: New partitioning - some feedback

On Fri, Jul 7, 2017 at 8:20 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> I don't have a strong view on whether partitions should be hidden by
>> default, although I lean slightly against it (say, -0.25). But if we
>> do decide to hide them by default, then I definitely want an
>> easy-to-use modifier that overrides that behavior, like being able to
>> type \d! or whatever to have them included after all.
>
> AIUI the user is responsible for DDL on partitions, like say creating
> indexes for them? Seems like hiding them is a bad idea given that.
> Also, we need to be careful about calling them something very separate
> from "table", because that would rouse the need to have duplicate syntax
> for every sort of ALTER TABLE and suchlike command that we want to have
> be usable with partitions. I think we've largely gone the wrong direction
> in that respect with respect to foreign tables and matviews.

Well, I'm not sure what other direction we could have taken there, and
I don't think it follows that just because it's labeled differently in
\d output it has to have different SQL syntax.

On the core question of whether they should be hidden, I think the
answer is that it depends on the situation. As Simon says, if people
use partitioning with large numbers of partitions, listing many
nearly-identical partition names clutters up the list to an extent
that makes life quite difficult; I've encountered this as a real
usability problem on actual systems. On the other hand, people with
more modest numbers of partitions (say, 10) might well find it more
convenient to see those names included, because they're legitimate
targets for commands like COMMENT and DROP TABLE and lots of other
things, and somebody might very well find it convenient to be able to
get that with \d rather than \d+ parent_table_name.

As I say, I don't feel hugely strongly about the default behavior, but
I do feel strongly that the idea that only one of the two proposed
behavior is useful is entirely incorrect.

--
Robert Haas
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