Re: Partition-wise join for join between (declaratively) partitioned tables

On Thu, Oct 5, 2017 at 7:18 PM, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> wrote:
> Robert Haas wrote:
>
>> Regarding nomenclature and my previous griping about wisdom, I was
>> wondering about just calling this a "partition join" like you have in
>> the regression test. So the GUC would be enable_partition_join, you'd
>> have generate_partition_join_paths(), etc. Basically just delete
>> "wise" throughout.
>
> If I understand correctly, what's being used here is the "-wise" suffix,
> unrelated to wisdom, which Merriam Webster lists as "adverb combining
> form" here https://www.merriam-webster.com/dictionary/wise (though you
> have to scroll down a lot), which is defined as
>
> 1 a :in the manner of * crabwise * fanwise
> b :in the position or direction of * slantwise * clockwise
> 2 :with regard to :in respect of * dollarwise
>

That's right.

> According to that, the right way to write this is "partitionwise join"
> (no dash), which means "join in respect of partitions", "join with
> regard to partitions".

Google lists mostly "partition wise" or "partition-wise" and very
rarely "partitionwise". The first being used in other DBMS literature.
The paper (there aren't many on this subject) I referred [1] uses
"partition-wise". It made more sense to replace " " or "-" with "_"
when syntax doesn't allow the first two. I am not against
"partitionwise" but I don't see any real reason why we should move
away from popular usage of this term.

[1] https://users.cs.duke.edu/~shivnath/papers/sigmod295-herodotou.pdf

--
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company