Re: Postgres 11: Table Partitioning and Primary Keys

On Tue, Jul 09, 2019 at 06:59:59PM -0400, Tom Lane wrote:
> Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
>> <listitem>
>> <para>
>> Unique constraints on partitioned tables (as well as primary keys)
>> must constrain all the partition key columns. This limitation exists
>> because <productname>PostgreSQL</productname> can only enforce
>> uniqueness in each partition individually.
>> </para>
>> </listitem>
>
>> I'm not really sure about the "must constrain" verbiage. Is that really
>> comprehensible?
>
> I think "must include" might be better.

+1.

>> which may not be the pinnacle of clarity, but took some time to craft
>> and I think is correct. Also it doesn't mention primary keys
>> explicitly; maybe we should patch it by adding "(as well as a primary
>> key)" right after "a unique constraint". Thoughts?
>
> I'd leave that alone. I don't think the parenthetical comment about
> primary keys in your new text is adding much either.

Agreed with not bothering about this block and not adding the
parenthetical comment.
--
Michael