Re: [HACKERS] Hash Functions

On Wed, May 17, 2017 at 11:35 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> I think the question is whether we are going to make a distinction between
> logical partitions (where the data division rule makes some sense to the
> user) and physical partitions (where it needn't).  I think it might be
> perfectly reasonable for those to behave differently.

Agreed. To summarize my perspective:

* hash partitioning offers a nice way to divide the data for later
processing by parallel query
* range partitioning is good for partition elimination
(constraint_exclusion) and separating hot/cold data (e.g. partitioning
on date)
* both offer some maintenance benefits (e.g. reindex one partition at
a time), though range partitioning seems like it offers better
flexibility here in some cases

I lean toward separating the concepts, but Robert is making some
reasonable arguments and I could be convinced.

Regards,   Jeff Davis