Re: Indexes on partitioned tables and foreign partitions

On Wed, May 9, 2018 at 9:08 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> How much sense is it to have a partitioned table with a mix of local
> and foreign tables?

Fair question, but we put some effort into making it work, so I think
it should keep working.

> Shouldn't the fix be to allow creation of indexes on foreign tables?
> (Maybe they would be virtual or foreign indexes??)

It might be useful to invent the concept of a foreign index, but not
for v11 a month after feature freeze.

For right now, I think the options are (1) throw an ERROR if we
encounter a foreign table or (2) silently skip the foreign table. I
think (2) is defensible for non-UNIQUE indexes, because the index is
just a performance optimization. However, for UNIQUE indexes, at
least, it seems like we'd better do (1), because a major point of such
an index is to enforce a constraint; we can't allege that we have such
a constraint if foreign tables are just silently skipped.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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