Hi Aron, >From what I understand by looking into RelDistributionImpl class is that it accepts the keys/columns on which the hash function is applied. Given the properties of a hash function, I would say that this information is sufficient for determining if a collocated join is possible. I don't think you need the exact partition number nor the specification of a hash function (assuming that everybody uses the same).
Best, Stamatis On Mon, Feb 3, 2020 at 4:20 PM JiaTao Tao <[email protected]> wrote: > Hi > > When I see the example of HASH_DISTRIBUTED, > e.g. RelDistributions.hash(ImmutableList.of(0)), or in > RelDistributionImpl#satisfies > I can't find the info about "hash partition num" of "hash func", if we > don't know these message, how can we perform a Bucket Join (Collocated > Join)? > Or do I miss something? > > Regards! > > Aron Tao >
